Most people can hand-hold a direct vision camera steadier than a reflex, for no reason I have ever been able to figure out, so yes, refles vs. RF does matter unless you always shoot in good light.
With an RF, effective base length matters, so you don't want a Noctilux or a 75 Summilux on any Bessa, or even a 50/1.5 on most of them if you're shooting close at full aperture. Longest EBL is the Zeiss, but Leicas are long enough.
If you want a meter, some are a lot better than others; I don't much care for the ZI meter (except on the SW).
After these practical considerations, it's easier to get good picture with the camera you like most, so yes, it matters in that sense, but equally, it doesn't preclude getting good picures with any other camera.
Cheers,
R.