I agree, the Meridian forum is a great place to learn about Meridian equipment, but we're a bit biased over there. You can visit at http://www.meridianunplugged.com
I own a pair of DSP8000s. I have heard some of the great speakers of the world, and if I had my choice of ANY of them, I'd own DP8000s. I think one of my friends said it best: "I've heard a lot of great sounding systems in my life, but yours is the first one that actually transports me to the performance."
In my opinion, not all Meridian DSP speaker models sound the same, so you should listen carefully to the various models to be sure that you like them. (Don't listen to 7000s and assume 5200s will sound the same, only smaller, for instance). The various models have been designed over a long period of time and with different cabinet technology, so you wouldn't expect them to all sound alike.
One thing I like about DSP speakers (and all active speakers) is that they take you off he merry-go-round of amps, cables, etc. I have owned active speakers for 20 years, and would never go back.
There's a great white paper on Meridian's website about active and DSP speakers (authored by Bob Stuart, founder of Meridian) that outlines their design philosophy clearly. It's a great read - highly recommended.
Enjoy - John