The SM58 was the first mic I bought. Figured I might as well go with a live classic, even though I would mainly use it for recording at home.
It does not disappoint. Perhaps I'm biased on account of owning one, but I feel it was a particularly good choice for me:
I like to think that I have some serious volume to my voice. The space in which I'm recording is small, and has pretty bad noise contamination (whine from computer fans and fridge). The SM58 allows me to isolate the vocals, and just record as loud as I feel like singing without worrying about peaking or background noise. I can see why some prefer a different vocal mic, but I very much like the sound it puts out; clear, focused, and yet a bit rugged (through Reason Balance interface).
The heft and build quality is outstanding. I tend to not be very gentle with my stuff, but I won't ever break it - it will break me first :)
The lack of features is the main feature. Couldn't be easier to use, and I understand it's easy to repair if needed.
I agree that this is a must-have!