bananaoil, yes, I did get good comfort, as long as the elastic I used was wide enough (1cm or 3/8" is the width this pattern uses, and I would say that is a bare minimum, except maybe for an A cup size or smaller). Making these yourself does allow you to choose your own materials, so you would be able to use whatever fabric and elastic you would find most comfortable. Also, if you have a very large cup size and small band that's hard to find in RTW, or vice versa, making your own might be a way to get a better fitting size. The downside is, fitting is definitely a trial and error process and you might have to make several before you get one that really fits well.
becca, it's definitely doable -- most RTW seems to use only straight stitch, zigzag and three-step zigzag. The only thing they have that we don't is a machine to stamp out molded cups (like on T-shirt bras).
I just remembered, I have another few pics that show fitting the cup onto an existing RTW bra... will add those to the album.8/1/11 8:04 AM