Where are you located? There is a message thread here that lists a lot of people willing to let you come over to their house for a listen. Even outside of that list, others may be willing to help you out, but we just need to know where you are located at.
As for a speaker comparison, you will be hard pressed to get a response of "it sounds like ...." since all speakers are different. Kind of like explaining to someone how your favorite lasagna tastes if they have never tasted the sauce or cheese you are using. You could say it is tomato based (which I hate tomatoes) with white cheese. If I had never had lasagna before, I would not like it based off of that description as I don't like tomatoes and many white cheeses are not my favorite either. Now, if I can get a sample of it, and I can start smelling how good it is, once I take a bite I will know that I like it, or maybe that I don't, but based off of a description of the sauce being like tomato paste and some white cheese, I am turned off without any real understanding of the lasagna as a whole.
Odd analogy, but you get the point. People can tell you what they sound similar too, but that is their personal experience and may differ from your own. Not just on what they like and don't like, but on their assessment of how closely they sound to another brand/model of speaker will be different than yours...
Let us know where you live and someone may be able to give you a demo.
As for 7.1, some people love it, some people don't notice much difference. 7.1 DVDs are few and far between. So before you jump to 7.1, weigh that in as well. If you have the cash to do it, go for it. Make sure that your room allows for proper speaker placement too. I was going to jump to 7.1, but my room didn't work for placement of the additional 2 speakers.
How high are the ceilings? Is the room totally enclosed (with closable doors) or is it open to other parts of the house? You need to look at total air volume, but my initial thought is that the M22 or M60 would work for mains. I almost got the M22 fronts but it was recommended by Alan at Axiom that for the air volume, I move up to something bigger so I went with the M60 fronts. I love them. THe VP150 is good too, and the QS8s are probably the BEST surround speaker out there.
