I used to use the Direwolf pack, but switched to Ultimate because I wanted to try out GT a little. I never got that far because I found it really hard, and when I used an "easy" configuration there was still the IC2 bronze nerf. Ultimately it came down to that and the jerk comment from GT that appears every time I start the game, so I removed it from the pack along with IC2 and a few other mods. Playing in my nice BC powered world. One thing I miss is flying though, waiting for MPS and TE to get a BC compatible charging station for it. It has forced me to look at other types of armor, really liking Twilight Forest's Ironwood.
I'm off on a tangent again. I use an IC2 free Ultimate pack, because TE has my machine needs covered.