Currently I am using a triple Kickstart selector (1.3, 2.04, 3.1). I may remove it and put in a double kickstart with 1.2 and 3.1.
For maximum compatibility with that setup, use 1.2, 1.3, and 3.1 in the Kickstart switcher. 99.9% of what works under 2.x will work under 3.1.