<p>Thanks everyone for the insight and thoughts. Since my original post, I spent some time in a Leica store comparing an MP to an M7. I also spoke with the sales guy for quite a length of time, as it turned out he was more at home with the film M bodies than the 240, etc.</p>
<p>I've summed up an answer to my question with the following two points: 1) It doesn't really matter as you'll get the hang of it regardless of which camera you choose; and 2) Going for whichever design is "faster" kind of misses the point of shooting a film rangefinder in this day and age. Sure, you want to be handy with your camera so you can get a picture without fiddling. But if speed is what's most important, other camera styles are probably more appropriate.</p>