Home Theater speaker choice? help

I am considering a few different home theater setups, JM labs with the Utopia Mini, Revel Performa Line, Thiels MCS1's,Snell XA1900c, any thoughts? recommendations, they will be going in a cabinet. I will be using a M&K 150THX sub.
You're saying that the L/C/R speakers will be going into an A/V cabinet? Also - is this strictly HT or is it for any sort of serious music listening as well? All the speakers you mention are pretty high-end if you're going to put them in an environment such as an A/V rack where you'll get far less than optimal performance. If this is mainly for HT (not much for serious music listening) you could probably save a fair amount of money and get similar performance from a more inexpensive line. I've never done the research on what speaker would best fit this approach - presumably they'd be at least front-ported or non-ported (tho speakers that small are usually ported somehow). Some speakers are designed to be placed in such an environment with less degradation.

Or, if I've misunderstood what you meant, you can ignore this :-)

The only high end speakers I've heard in a cabinet were Monitor Audio Studio 60s. Most speakers sound horrible in a cabinet. These did not, however, they do sound much better out in a room. The transmission line on the Revel's and Thiels would have me believe they would be a bad choice for cabinet placement. The Snell's are probably a little better, but you might check out the Monitor's.