I was told that anyone who wears both is 100% guaranteed to be a Republican. In my observations this is true, but YMMV.Suspenders with a belt can work. I've used them if I have a particularly heavy load to support on the belt, i.e. lots of stuff.
One "catch" with suspenders might be if you carry appendix.
Suspenders don't work very well with appendix carry, imho, since one of the front suspender straps can easily foul your draw (and will eventually).