For the most part, it is believed that they overate their packs, meaning that something they rate as 25c could really be 20c. Their prices are also higher compared to similar packs.
MaxAmps 35c 4200 MAH 6s pack, $339:
http://www.maxamps.com/Lipo-4200-222-Flight-Pack.htm
FullyMax 35c 4400 MAH 6s pack, $239:
http://www.impaktrc.com/product_info...oducts_id=4545
PolyQuest 25c 5000 MAH 6s pack, $294:
http://www.rc-monster.com/proddetail...pq25c6s5000mah
Hope this helps.