I'm pretty sure I'm repeating myself, but even purely on a technical level, I'd have to disagree.
As per the
RF accuracy chart, any Barnack with a 1.5x magnified viewfinder actually has more accurate focusing than any M other than the M3 (and even compared to the M3, it's close). If you're using Canon's 135/3.5, any 0.72x M actually falls short of being able to focus it reliably wide open, according to the chart. Using it on my M240, I have to agree.
The only real downside to the Barnack's short baselength, high-mag setup is that the rangefinder has to be calibrated correctly. But as a side bonus, the Barnack design is
much easier to calibrate at home - and much easier to calibrate
accurately, too.