Also, 5 bikers, even with a 3++, 5+ fnp are easily crippled
(just 2 poor rolls will hurt the unit attack or defens capability) and since i'm not going to waste ap3 on the guys... just some autocannons aregoing to ruin your beautiful 3++ unit.
So, unless joined by a beatstick HQ, i'd go for the 2 MSU.
But is it easier to cripple 5 T5 3+/3++/5+ FnP bodies than it is to cripple 6 T5 3+/4+ cover bodies? I'm not sure it is. Worth considering for sure, but if I pick up another box I can build the dudes necessary to run both and playtest them - that's where I'll really find out
Thanks for the input though, both of you.