[markem]

I don't know about how others pick their smokes, but I tend to pick based on:

1. It has a flavor I am interested in
2. I have time to finish it

RG, length, etc. may go in to #1, but are not normally a standalone criterion. Mind you, sometimes on skype we'll pick a theme such as CE, lonsdale, etc. but that is more the exception than the rule.