Kind of interesting, really. For the longest time the Owens B was the starter mech. The C was extremely uncommon, and didn't take over until the price fell just a tiny bit - into the rank 1 bracket. Similar stories for other mechs. The Uller A jumped a tad over the rank 1 threshold and went from ubiquitous to very rare, the Uller prime dropped down and now it's...well, at least not totally unheard of. Gone also are the swarms of Puma and Cougar As. Goes to show how sharp that first rank dividing line is...
Personally I tend to prefer less common mechs, just for fun. So right now...B variant, usually.