I had the RD-1 digi rangefinder, built on a Bessa. To be honest, there was nothing plasticky about it. Well built, in fact more so than many a camera of yore. However there may be two issues. Paint job is not the best, wears off on corners. But the body is a dull gunmetall grey, so it "brasses" quite nicely really. And the rangefinder (on RD-1's at least) could get knocked out of alignment. Though very easy to fix. Mine I tuned when I got it, and never again.
Nice camera, good heft, and very good viewfinder. Parallax corrected framelines. If I didn't already have a Leica M, I would be getting one, one with a large magnification finder for wide angles.