IMHO -
If you're going to houses that you don't bowl at frequently and had to buy a replacement sole or heel for either a Dexter or a G3 shoe most shops I'm familiar with usually have Dexter replacement heels and soles. That isn't to say there aren't shops with ABS/Dyno/G3 stuff as well, I just don't see those as often as Dexter stuff.
If you have ever considered switching hands the SST8's are the only shoes, to my knowledge, on the market that let a bowler switch slide/traction soles between the left and right shoes. A guy I'm currently bowling with has them for that specific reason.
On the other hand, I've heard great things about the G3 shoes. Unfortunately no one in my local area stocks them, so I can't personally try them for size and usability.