It all comes down to how much homework you want to do and what your partners are using. All the mic's mentioned are really good, but the SM58's are standard in the performance field. SM 57's are the same mic, with a different ball on the end. The Shures aren't the best around these days but they sound good in any system, pretty much always sound alike and, if you play a lot of different places, the majority of the house mics will be 58's. And you can pound nails with them.

Beta 58's are a lot more responsive. The EQ will be a lot different.