I'm flying with HC Zippy 5000mAh 25C packs and they rock, expecially if you take the price into the consideration.

25C means 125A continous current, while the standard WindS setup (Masterbasic 90/A50-16L) never pulls more than 70 amps with an APC-E 18x10. I usually fly about 8 minutes and then charge 2500~3000mAh, so plenty of reserve. The 5000mAh is nice to get the CG correct.

Only abuse I do do on them, is charge them with 7A instead of 5A. Both packs are at about 90 cycles now and there's no noticable wear yet. I expect to get at least 150~200 cycles out of them.