Without having any experience with these batteries its impossible to say how they fair, especially if we do not know who the manufacturer of the cells are.
The prices of these packs seem pretty comparable to most other lipo's so I'd say, for those prices, they'd better perform up to par.
Give those Maxamps a try and post your findings here.
Castle Neu 1520 on 6S LiPo Powered Gmaxx (Nitro Killer)
Predator with OS .21TM
Supermaxx with Mach .26
Revo with OS .18TZ
Kyosho ST-RR Conversion
Ofna CR with Tekin ESC/Motor (2)