The R3 is, for some people, an entry to the Leica SLR world. In the U.S. at least the R3 has a very poor reputation for reliability. It also does not have user interchangeable focusing screens. Leica SLR lenses are available but expensive so you have to consider how many of them you can afford and whether that selection wil be adequate for the kind of shooting you do. There are probably more Leica SLR users who like the lenses than ones who like the bodies. The exceptions might be the SL, SL2 (+MOT versions), the R8 and the R9.