I don’t think there’s all that much practical difference between them these days.
I use Firefox, without Flash installed. With Flash I found Firefox to be badly unstable, it’s been solid since I removed it. Plus it safeguards against malicious code. I switch to IE for work systems (because they’re Microsofty and don’t play well with others) and for anything that needs Flash. The sooner Flash is properly dead the better, IMHO.
FF and Chrome seem to be largely interchangeable; I don’t use Chrome mostly because I’ve not really seen any need to switch to it rather than there being anything inherently wrong with it.