I buy 2 at the start of every game.

Edit: The best is using them at the start to draw people back in the 1st encounter. People flip when they think they can get an early kill.

I personally prefer the 3sec cast, 400g, 3000 heal ones.

Pffft.  Potions are inefficient, only useful if you're able to trick an opponent into overextending.  In other words, only useful against noobs.

Better off investing in items that will give you a long return, like Scalemail or Banded Armor.

Potions can be good stop gaps for certain builds.  For instance, when I play beast with blade of the serpent, I'm a little more vulnerable in the firwst 2 or 3 levels, and will sometimes pick up a combat health potion or two.

Similarly, if I see an enemy player that 'over-chases' a lot, or tries to kill swap, I may pick up an extra potion.  It isn't just about surviving, you can use them to trap people as well.

The other item I've been really surprised by lately is the sigil of vitality.  Instant case item that gives a boost = to half your total health for the duration of most combats. It surprises the HECK out of an opponent. Also, I don't think it can kill you when it wears off (Though it will drop your health down very low). I might be wrong about that last point, but it is pretty sweet.

Potions aren't just lures, they provide staying power in the early game. If I buy a set of potions, and you jump straight to armor and a helm, I can probably harass you into going back to the base, losing effective gold and XP you could have had if you bought potions. In this regard, they're even useful in "pro" (the game's been out what, 2 months?) games.

potions are one of the rewards you get for managing to play a cheap item build effectively. you can juice your citadel or buy consumables with the extra gold. either way you get nice bonuses. 

i seriously think more people should learn to make due on minimum item purchases. you'd be amazed how far you can get on just Banded Armor and Scaled Helm if you're judicious about skill usage and pick your fights wisely. 

WTF?

Dude, look at the math.  The early stuff is the best stuff.  Banded Armor gives you 72 health per 100 gold spent.  The next most efficient item is Unbreakable Boots at 40 health per 100 gold spent.  Buy the Banded Armor, use it early game.  When you need a little space, sell it and get 320 gold back.  All the other items cost alot more for alot less.

Thanks for speaking for me but you got it wrong:  I realize that spending 300ish gold can net you a kill.  If it does that, it pays for itself and you get a return on your investment.  I also realize that it can deprieve the enemy of a kill.  And yea, it can do more than that.  It can help you drive a DG out of a lane, netting you creep XP and gold.

But a potion does that once.  After that first encounter, you won't get anything else out of the potion.  It's gone.  Banded Armor or Scaled Helm or whatever else gives its goodness over and over.  In every encounter, Banded Armor gives me an extra 400 HP.  After 2 encounters at full health, Banded Armor has given me an additional 800 HP for 550 GP, breaking close to even with a potion.  And it keeps getting value.

Obviously, I can get Banded Armor and a potion.  But I've got to give up something for the potion.  The same reasoning applies to all the other items but it's more difficult to compare value because they don't modify the same stat.  So if I choose to forego Scaled Helm for my potion, my reasoning still applies.

This is a constructive comment (make note woca).  Instead of disparaging my assumed understanding of the game and assuming I'm not willing to discuss the issue at hand, transitive suggests a scenario under which potions are viable.

It's a good point.  I still disagree - I still prefer to spend my money on something that's going to stick around.  If I've got a little extra, I'd rather buy Tower Health or save it for a slightly earlier Vlemish Faceguard.

On a bigger map with multiple gold mines you control at the start, such as Zikurat, I'll hang around at the base for a few extra seconds so I can afford a combat potion in addition to my starting items.

If I'm taking serpent I don't much need the helm on many characters. I'd gladly sacrifice that for a couple potions.

i really like to open on Banded Armor no matter what DG i'm playing. 

whether i go for potions, scalemail, or scaled helm will depend on the map and my build. 

but discussing the starting options isn't even such a useful thing. i was trying to think about more along the lines of how much money you'll budget for potions throughout the whole game. you can save for better gear or you can get consumables for immediate payoff.

i'm still not sure i know which way has better results. its part of the depth of this game. interesting topic for discussion. 

Maybe so.  I look at it this way:  Potions provide a one-time high impact benefit in the early-mid game.  Persistent items provide a repeatible moderate impact in the early-mid game.  It's analagous to sprinting versus long distance running, burst damage versus sustained damage, living wild and care-free versus planning for the future.

Knowing the roles potions play relative to persistent items will help you decide what you need to invest in.

My experience has been that the good players don't overextend - they assume you have a potion.  So the usefulness of a potion is lessened.  I default to persistent items 80% of the time.

Winning this game against the best players requires you to maximize your effectiveness at all points of the game.  Potions are very effective for this early game.  Good players will solidify their advantage very early game, often by level 5.  If you really think that you have gained an advantage by forcing someone to burn a potion while you back to the fountain, you are a fool.  Consider this:

In the minute it takes you to run to the fountain, heal, and come back, I will keep or cap the flag, gain a good xp advantage, and earn gold by killing creeps.  Depending on who I am, I may knock your tower down in that time.  If I get up in level early game, your extra banded armor doesnt compensate.  All that really matters early game is experience, war score, and space (as defined by how many towers are left and thus how far I can chase you).  The way to obtain these things is to win encounters, 1 at a time, usually over flags, and to stay on the front lines.  In many cases (but not all), potions do this for you better than armor.  I would rather be 2 levels up and 1000 gold short by mid game because thats an easy victory for me.

As some have mentioned, low cost armors are usually the best deal, and, in the long term, can be calculated to be more hp/cost effective than potions.  I agree with you, low cost items are the best bang for your buck.  When buying persistent items, you should fill your inventory with low cost items first, and slowly replace them with more expensive items to fit your needs.  However, when doing your cost/reward calculations, you have to consider the battle winning effect you get with potions.  With potions, assuming you are using them properly, you are not just purchasing XX health/$ or XX mana/$, if they work, you are purchasing time, experience, and war score.

Potions dont work for everyone, and I am not advocating them under all circumstances.  I always look to see which enemy DG's I am fighting before I make initial purchases and choose the items that fit them.  For example, enemy UBs and I am any assassin? - Probably BOF, Banded, 2xMana Pots, with generals it would be similar but I would buy/summon/sell monks.  Am I fighting burst damage on the other team (e.g. Oak/TB, Sedna/TB)? I am probably getting health potions. 

Potions can certainly provide you a strong early game advantage, and, if you are the type of person who likes to win early/mid game, thats what you want.

Potions and consumables in general begin to lose their "in combat" use when all but 2 of the DG in the game have the ability to interrupt them by mid-game.

Consumables are always great outside of combat, but relying on them during combat past early-game will only get you killed if you're against more experienced players who know how to interrupt.