Bought my CHM-s630 brand new at onlinecarstereo.com for $189 with free shipping. VOLALP interface cable can be purchased easily on-line for $25.
Fits like a glove in my glovebox, go figure.

My Alpine CTMS630 is mounted in the trunk below the rear deck, near the antenna. This is also where the stereo shop mounted my old changer in the 940 sedan.

My unit cost $200 new. A suggestion is that you know the unit you're buying is new or hasn't been in a wreck. We pulled my almost new 620 changer out of the 940 that was rear-ended (not a scratch on the changer)and installed it in the 850, only to find that the crash shifted the laser beaam beyond what the unit could be adjusted.) It was was either have it repaired for $250 or buy new for $210.

Suzanne

I installed the Alpine CD changer in my 95 850 earlier this year. Paid about $180 on e-bay and purchased an adapter for about $50 from a local stereo shop.

I installed mine in the trunk under the rear deck. I used some of the existing speaker screws to mount the unit. Very easy installation. The advantage of this location is that it is out of the way, yet easy to access. You can't even see the unit with the trunk open. it also doesn't get the abuse that it would receive if mounted on the floor of the trunk. It wouldn't fit in the glove box, so that wasn't even a consideration.

I'm also interested in finding out where people have been mounting their cd changers.

The $270 seems high. I just purchased an Alpine s620 and an adapter (VOLALP) that I will be installing into my 1995 855 for $105. The alpine off of ebay and the adapter at sounddomain. I will also be using the sc811 head unit.