Yeah, don't bother. I've got a friend with a BE Steyr, and I would take the JG to that anyday, thanks to the airsoftreports video. The gearbox sounds a bit strange from the JG video, but to me, it sounds to be very quiet.
Anyway, the BE steyr has a high ROF, but not so good distance. I think the FPS is right around 280-290, im not sure, check AS-Retreat. I custom installed a hopup screw, since the factory setting wasn't quite so good, and we have achieved quite an increase in distance. It's not a difficult mod to do at all, just set in a flat topped screw into a drilled hole in the hopup chamber above the bucking, and the screw will press down on the BB more.
Range and accuracy increased after the mod, though it was still showing a shorter distance compared to some of the other guns. I can say that after the screw installment that it shot better than most of the other clones on the field, again, noting a nice ROF.
JG, IMHO, still has it beat. Higher FPS, and according to the airsoft reports video, extremely high accuracy, just watch the BB's hitting the 200' target. And for only a few dollars more, It looks to be worth it.
I have no idea about their other guns, but I'd be assured they've just got similar internals, so you can bet that they're not going to be too great.