5.8.3 on WinXP
5.8.6 on Win2K
5.8.5 on FreeBSD 5.3
5.8.0 on FreeBSD 4.8
5.6.? maybe on the Mac at home-- haven't used that in a while.

I use these simply because they were convenient at the time.
I'm not using any bleeding- or even cutting-edge features, so I just take what's easiest to find.