Unfortunately with true dedicated mogul skis it's not possible to really demo them. Which leaves you with three choices: recommendation by people you know & trust who have skied the skis (very few or none for most folks), recommendation from folks on boards like these, or "when in doubt ski what Bloom skis."
I'll be the first in the second option. I'm pretty close to your size (6'0" 200), and I've been on the dynastar twister in moguls for 2 years now. It rocks, but don't take it out of the moguls (except maybe into tight trees on hard pack). I have rarely used them this year though, as they are really awful on everything but moguls, I can't ski moguls all day (between a crappy knee and less than ideal conditioning it ain't happening) and it's kind of a pain to switch out skis a couple times during the day. So I ski the 8000, which is very good in the moguls and tackles the rest of the mountain pretty darn well too.
On the third option, I heard a rumor last month that volkl is supposed to be introducing a new mogul ski designed for/with Bloom. Or you could go with the girls' olympic results, I think the top 5 were 2 rossi's, 1 line and 2 dynastars.