The 3G Opaque has a softer hand. This was actually the first transfer that I used and it's pretty good. I'm currently trying out the Coastal Inkjet Opaque, and the issue that I'm having with it apart from the "sticker" feel, is the shirt seems to be showing thought the transfer. I've tried following the instructions, but maybe I'm doing something wrong.
Anyway, I'd go with the 3G Opaque transfer paper.