I'm sitting here pricing lcd monitors and you get much more bang for your buck with the smaller ones.
I have two 15" lcds and thought about getting two additional 17" lcds. But after I thought about it in terms of $ per sq. in of screen, I could buy 4 more 15" lcds for the price of 2 17".
So what's your preference, a few big ones or a lot of little ones?
3 17" monitors work for me. I don't think I could follow 6 15" monitors. I like 3 17" monitors set a 1024X768.