Well, we played a game vs a mid-pro team (Dark_Satana, Quincrane, Pupsik), and both Cape QoT and Vial Rook got slaughtered over and over again. We had Vent, and the Rook had tons of mana, but it didn't help much in short skirmishes. The guys were so overly respectful to us, that they picked UB/Ereb/Oak combo vs our experimental Rook/Sed/TB, so it was a more-or-less lost game from the very beginning, but we didn't expect it to turn into a massacre so soon 
Surprisingly enough, Cape Sedna and Renewal Rook (+random Vent-less mid UB, as SeaWolf wasn't available) were much more successful against UB/Ereb/Occ (same players). We were pushing hard as hell, and probably could have won that one, but the lack of coordination between us and the Vent-less UB was horrible, and when we were forced to split, both Cape Sed and Renewal Rook were somewhat sub-optimal on their own.