I know this isn't exactly pertinent to the topic at hand, but you might as well play around with a few different positions.
I know I use a big arch and really tucked form, and all that did was make my chest look smaller and fucked with my lower back.
I tried tucking harder and using a smaller arch, and that was okay. Eventually I just found a great sweet spot. I know everyone's different when it comes to that... even things like feet position, etc.
Also, Suicide Grip FTW.