Well lot's of people say "I'll never get a...", but after a week they turn around and wish they had. You can apply the same logic to the 755 vs the 7100 with regards to paying for what you will not use. Are you going to ever use that much power above and beyond what the 7100 can do? If you're never going to use the power you can save the money and have the two extra channels just in case you do go to 7.1 later on. Are your speakers inefficient and/or do you have a larger room to fill? If I did that with my speakers I'd be able to use the extra 2 channels on the mains as I can bi-wire/bi-amp mine, so those would get more power and the other 3 speakers would get a smaller, more appropriate amount of power.

I'm just playing a little devil's advocate to show the other side. silver did say he's new to HT. Many times people don't quite know what they want inspite of what they may think at first. He can add a pair of M200's later on if he does decides to go to 7 if he got the 755. It'd just cost even more money.

Would the size and/or weight of either unit be a problem?