Two years on, they are probably even more difficult to have repaired, although there seems to be something of a film resurgence (hah! - at least in my household).
R bodies are now so cheap and readily available that professional repair has to be uneconomic. However, in my experience the R series cameras from the later R4 model onwards are pretty reliable, despite their age. All I have seen with mine is failed viewfinder metering mode indication LEDs (no great problem, as the body in question continues to function normally) and isolated incidents of the shutter speed indication and frame counter going awry.
If you are determined and have a steady hand, either of the latter problems are easily fixed by taking off the top plate and relocating the comedy fishing line that pulls out the tape on which the speeds are printed (I am not joking!) or retensioning the rather weak return spring of the frame counter.
Otherwise, of course, you can bin the thing and replace it for £100/$100 or less (I've seen a really nice, rare-ish R4S Mod P on sale for just £89 in recent weeks).
My tips to preserve these fine cameras in working order are: replace the film window and opening-back light seals with any one of the cheapo eBay kits (a really easy DIY job) and always leave the camera with the shutter wound right down to the orange, mechanical default 1/100th setting (which takes all the tension off the speed readout tape) and the frame counter set to 'S'/zero (ditto for the weak return spring).
Oh, and when it comes to which one to buy as a replacement, as the books don't say, the late-model (post '85 is my estimate) R4 has both the much brighter screen fitted to the R4S Mod 2/Mod P and - for all us obsessive Leica nuts - the dinky cast red-dot badge fitted to the R5 and later, improved R models.
So; enjoy!