Kstnbike:Thank you for your responses. I think most of you have convinced me to go with the back inflate. The only problem I had with it when trying it on was it was a little tight around the waist (I am a skinny guy too) which was kind of a turn off. Might have just been the way I was wearing it though.
Thanks,
Kstnbike
If it was tight in the shop (presumably with clothes) be sure to try it with the exposure protection you intend to use before buying!