Sometimes it helps me feel more comfortable, and other times it makes me feel really dysphoric. Depends, I guess. Right now I wouldn't know as I've lost my dick >.< transguy problems...
I don't think it helps me feel more masculine--I don't always feel or want to feel masculine. I can be feeling really femme but want to pack, for me it's more about body comfort and male-ness as I define it for myself.