Best LiPo for Cat SX2 - Stubby LiPo?

[RandomConflict]

Hi guys,

Advice needed. I have just brought a second hand Cat SX2 and wondered what LiPo batteries you guys would recommend. I currently have Xcelorin 6000mah stick packs, but these seem a little to thick, and although they miss the middle belt and pulleys, they rub against the front belt where it drops down through the centre.

Are there any other stick packs which you guys know will fit? Also, what do you reckon to the Stubby LiPos. I'm pretty impressed so far with the Xcelorin packs I have and was considering the stubby version (this would also allow me to move the battery back and forth for different weight distribution). My only concern was however whether they would be up to the job? I run 6.5/8.5 brushless and believe they are only 3800mah capacity. Would they last 6/7 minutes of running easily or would they cut out on me due to low voltage near the end of the run?

Any info greatly appreciated!

Many thanks,

Alex