I have never gotten a pack of batteries that cycled out to the numbers on the label. They always seem to be off by 10-15 seconds this goes all the way back to 1700 SCRC's. I've rematched packs using a TM 4/35 and then cycled them (once it's built) and sure enough they're off by about 10-15 seconds. I belive this is cause by 2 different reasons. 1. Is simple a TM 4/35 is a dedicated unit only matces batteries while the GFX does all kinds of stuff so they're gonna be some variables. 2. This is just something I think and that is on the TM 4/35 you have each cell charged individually while on the GFX you're cycling as a pack causing more variables.
I get packs and run them a few times. If I know that I wont run them for a while I will got through and cycle them this way I can compare them to eachother, but don't get hung up on the lable.
P.S. check out DC motorsports a link to the site can be found on my sig. I've had fantastic results with thier batteries.
follow me @RC3grafix on Instagram for pictures of my paint work.