Which speakers do I pick and are they close in quality

For about the same money as the M30.2 anniversary edition you could get the ordinary Harbeth Super HL5+. In a largish room such as yours, it would probably be a better buy.

I doubt that you will go wrong with the Harbeth. I own the smaller P3ESR and it blows away any other small monitor that I have owned. Here is a review of the M30.1. It is basically the same speaker as the M30.2!
http://www.theabsolutesound.com/articles/harbeth-monitor-301-loudspeaker/
And another!
http://www.6moons.com/audioreviews/harbeth5/1.html

This is like asking "should I buy a Ferrari or a Bentley?"  And the answer is the same -- it depends.  What are your priorities and preferences in sound reproduction and speaker characteristics?  Until we -- and hopefully and more importantly, you -- have a clearer handle on these things you're not going to get any meaningful advice or recommendations here.  

+1 Harbeth for softer FM sound. Great mid range. 

You don't elaborate on how you came to narrow the choice down to these two.  Are you buying new or second-hand?  Are these two models that are available to you?  They seem so far away from each other in the spectrum of speakers that the pairing seems odd.  And while it irritates me when other people do this, I'll break my own rule and agree with @willemj  re. the SLH5+.