you can get decent heel clearance with some chainstay dimensions if you don't go for deep panniers. Given that you're looking at some bikes that are close to road bikes with caliper brakes consider a small front rack like this for a compression bags worth of stuff

http://store.velo-orange.com/index.p...ess-steel.html

and then smaller panniers like these

http://www.jandd.com/detail.asp?PRODUCT_ID=FSBP

I toured for a month with that size of panniers, a medium sized handlebar bag(which could be the compression bag size on the minifront rack) and the rest on the rear rack. If you put all that amount of gear into big rear mounted panniers on a sport bike the handling is a bit funky.