matrix 803's.. i have chance to buy... worth it?

hello... i have a chance to buy a set of 803's and a matching center channel. i use my speakers for home theater only. i currently have cdm cnt 1's for the front and a 600 series center. if these matrix speakers are in good condition, my questions are
1) are these much better than my newer cdms? i have a sub...
2) how do these rate to the newer 800 nautilus series... not the diamonds can't afford them right now...
3) what is a good price for them? was thinking if i do not like them maybe i could sell them to help with the nautilus purchase. they are the black finish...

thank you for the help
B&W's are some of the best sounding speakers i ever heard when i was first getting into considering a high-end system- one example was the 802M series 2. BUT this was when listening
to a Bruckner symphony (#9) and not a movie soundtrack. powerful, tight, and
nearly impossible to overdrive. depending on the condition of these 803's as well as the condition of the cabinets you will have only one other problem- they magnify flaws in recordings and upstream components just like a good studio monitor is supposed to.
I should add that when comparing the Matrix 803 s2 to the Nautilus and Diamonds, I've actually preferred the Matrix and Nautilus. I've found the entire Diamond line to be a little too bright for my taste. The Matrix series has plenty of punch and and the tonal balance is pleasing. Essentially, I've found them to have plenty of detail without being fatiguing. The Nautilus is somewhere in the middle, so if your preference leans toward the ultra-detailed and you don't get fatigued easily, maybe you'd prefer them; however, you'll pay a bigger chunk of cash for a speaker that you might not prefer.
Jazzerdave, great response. that is what I am looking for. Now what price? and what amp? or amps? I have a pioneer elite 92txh that I can bi- amp or I have pre-outs to run seprate amps off of my receiver. what ya think?

Where are you located? I think I know which speakers you are referring to and they are in great shape from the photos seller sent me. Very good price for the left-center-right speakers.

Goodluck with them,