I've got a JCM 900 that is actually for sale right now. It was the first Marshall Half Stack I bought (back around '94), and I was young and didn't really know what sound I wanted. The 900 is not a horrible amp, but it's not close to being Marshall's best. I still like the 900 better than the JCM 2000's, but nothing compares to a JCM 800.

The 900's are very muddy sounding, the low's are "flabby", and contrary to the sticker on the front that say's "High Gain", it is not a high gain amp. The clean channel is very thin sounding also...