I had a 3630 which was a somewhat wide deskside tower, no louder than a deskside Sun 3. I never had any service problems other than a somewhat dubious tape drive.
3630 was second generation design, a so-called "G-machine" (vs. "L-machine" of previous models), and I believe it already shipped with Ephemeral GC from start.
I was advised that if possible, grab the boards necessary to upgrade 3600 to 3670 to have much easier life ;)
