For the last few months I've been wearing underworks binders. I have a tritop and a 988 (the one that looks like a singlet and only compresses in the top). I've had issues the whole time with restricted breathing, painful rubbing under the armpits, sore back and shoulders and just general discomfort when I wear them. I also kept getting the dreaded uniboob and having to constantly adjust myself to stop from having a weird bump in the middle of my chest.
I decided to try out a couple of binders from www.lesloveboat.com instead as I figured they might be more comfortable. I got the "Original Jersey Mesh Velcro Short Binder" and the "Sports Pullover Short Binder". Both of them are so much more comfortable than the underworks ones were. I feel like I can breath completely freely, nothing rubs or chafes, it barely feels like I'm being compressed at all. When I first put them on I thought I must have got a size too big. Despite this they seem to do just as good a job of binding as the underworks ones did. Maybe not quite as flat but much more normal looking as they aren't cramming my chest into one weird lump.
I'm pretty small chested, around about a B cup, so I couldn't vouch for how well these will work for bigger guys but for me they're great.
I think they are excellent binders though they are $$$ and no good (i believe) if you are over about a C chest. They seem to bind okay. (I used the Air max pullover).
--Jay
They can be pricey, but so worth it. I got the Air M pull over in I think the summer of 2011 and it has been one of the smartest investments I've made. It keeps me cool in the summers because of the back being well ventilated and it keeps me nice and flat (or at least gives the impression I have good pecs).