You people are a bad influence. Been waiting on a Super Angulon R F3.4 for more than a week now, customs from Canada to the US takes forever!
Why did I end up with an R version? It's a long story. For some reason, a local farm auction had a Leicaflex Standard with lenses. I ended up with only the lenses (50 and 90), which were single cam, so I got a beautiful condition Leicaflex Standard Mark II from Westborn Camera, sent to DAG for a meter overhaul.
My plan is to use it on both the Leicaflex, my M5 (with a modified R to M adapter to prevent the meter from popping up) and my Ricoh GXR.
R version is scale focus only, but, with a 21mm, should be a bit easier.
I've been thinking about a full frame digital for a while, but I read that this lens won't even physically mount on the Leica SL. Can anyone confirm? The rear element should be pretty close between the M and R versions.