LSD is obviously a bonus and no matter what battery you buy you might only get a few extra mAh out of the battery. I doubt anyone touches Eneloops for quality, consistency or shelf life. They aren't the most expensive AA NiMH battery - but they probably should be. I only have 8 of the Powerex and 32 Eneloops. Buying more Eneloops soon. If not for some very specific uses I wouldn't even have the 8 Powerex so I understand an Eneloop only philosophy.
...but Powerex is a pretty good battery for what it is.
As for the paintball gun issue - The 9.6 V Powerex version seems to be the category winner (at least back in 2003).
http://www.warpig.com/paintball/technical/misc/maha9v/index.shtml
Not sure how the Imedion version stacks up. Both 9.6V's are listed at 230 mAh, but the Powerex is probably using a 'typical' rating while the Imedion is using a maximum rating. For instance, the Powerex D size battery says 11,000 mAh typical. The Imedion D says 9500 mAh and then minimum 8600 mAh in smaller letters. Sneaky bastids!
You might want to try the 8.4V version too. If 8.4V is enough to run the paintball hopper then you might get longer runtime with the lower voltage/higher mAh version of the 9V. From what little I've read of the subject voltage seems like the bigger issue and they go for the 9.6V.