Music Reference RM9 - user comments please

Back in the '80s I evaluated and bought a RM-9 to replace my restored Marantz 8B. It drove my Vandersteen 2 (whatever was latest version at the time). Beautiful sounding and looking, I might still own it except I bought larger speakers for which 100 wpc was not sufficient.

Looking back, it was one of the finest pieces of gear I've owned in over 40 years in this hobby.

I'll say one thing, I've never heard a bad word said about a MR amp by anyone who has owned one.

Nice to see a current thread about this amp. I've owned the RM9 for just a few months, after buying it from the 2nd owner here on A'gon. I'm only a couple of years in the hobby, so no expert my any means; but no complaints about this amp. Love the looks of it in the dark (never put the cage on after I got it - looks like a cityscape at night) It came with RAM labs 6550's in it and am wondering what I might expect if I changed to KT 88's. Anyone care to give an opinion?
CD source is a Shanling T80 with RCA black gates, fed directly into the amp, through some TaraLab cables to Quad 22L2 speakers.
Has anyone experimented with different driver tubes?
Thanks in advance for any input.

I changed the driver tubes to 6n23p and I love them.Troy

I have sold my RM10 and a RM9 MKII is on the way. I am very interested to see how it compares with my CAT JL2 - it owuld be nice to go from 16 output tube to 8; if the sound is of comparable performance.