They are durable cameras, although the rangefinder is prone to misalignment, and the earlier models with painted markings, rather than inscribed, didn't fare too well.
However, each model's quality of construction improved, and the cameras continue to be quite usable, despite missing paint and misaligned rangefinders.
I've had an L, R and R2 clone (Rollei 35 RF), and each has been a very nice camera. Predictable and for the most part free of mechanical issues. Meters are accurate and viewfinders are large and suitably bright.
They are good value for the money.
I'm toying with the idea of getting an RF. I'm an SLR guy. Been shooting them since the 70's. I have a couple of Argus C3's though and that's as far as my RF experience goes. I'm working to get the RF's and focus calibrated on those now. One was my father's he bought in the early 50's and the other I got at Goodwill when I couldn't get my father's to focus properly. The one I got at Goodwill has focus issues as well. I've been working on calibrating the RF on these but it has been a challenge to say the least. Today I will be shooting my 4th roll of HP5 to see if my last adjustments this morning worked. When I'm done I will have spent more on film than I did on the camera....
Off Topic -- Success. I finally got one C3 to focus. Now that I have it figured out getting the second one to follow suit should not be an issue.