Shouldn't take that long to install or uninstall one (unless there are problems..)
My vote goes to Avast; I think the free version is probably as good or better than the paid version of AVG. But it's all subjective, of course, until you get hit by something and your AV doesn't stop it. (Happens with them all, if you're real unlucky.)
If you're happy with AVG keep using it.
No reason why you shouldn't hang on to the installer files for the other AV's if you later change your mind, if bandwidth is an issue.
AV-Comparatives - Independent Tests of Anti-Virus Software - Welcome to AV-Comparatives.org is a fairly good site for comparing the performance of various paid AV's.