The Magnus Rod is what all of you mana-dependent HoL users should try using. If you look at the stats, it may not seem terribly impressive at first glance.
First, it has a pretty good passive, +50% mana regen. Also, it's active ability means that your mana regen only needs to work half as hard to refill the mana you use. Spells that cost 400 mana now only cost 200 mana with the Magnus Rod. If your mana regen is 20 mana a second, you refill your mana in 10 seconds instead of 20. I've found that I only need a Vlemish and a Magnus Rod for my mana-heavy builds. Plus, it uses a consumable slot and leaves your gearslots free.