Dude, there are a lot of audio engineers on this board...
58's have a lot of good qualities, but they're not always the best mic for every voice. True, a 58 will always sound ok, but I like to aim a little higher than "ok".
OK I'll give you that.
Ok, here's why I get a little up in arms about the fancy vocal mics:
I have my eq's set for 58's I have my compressors set for 58's, I have my gain structure set for 58's... if you want to use another mic that's fine, I'm totally down with that, but it seems that 9 times out of 10 the person that shows up with the condenser that feedsback in the monitor and has uncontrollable EQ problems is the person that shows up 5 minutes before doors open so I don't have the chance to make it work for them. Then they complain loudly about how it sounds bad.
If you use a mic that's drastically different than a 58 (I'm not talking OM2's, MD431's, stuff like that) then get there early so we can work on it. Otherwise you're subject to funky conditions.
I'm a damn good sound guy with years of experience, so please don't misread what I'm saying. Perhaps I didn't make my point.
The 58 is a good mic. It's not a great mic. But it's good for stage and it's reliable and easy to use. And 99% of the venues out there are using them. So if you want ease, get a 58. If you want something nicer, that's awesome! Just get something similar in design to a 58. And by that I mean, similar EQ curve, similar output levels, and certainly the same (or better) feedback rejection.
Avoid the mics that are too good for their own good. Like the Neumann vocal stage condensors. Great mics! But they require the sound guy to tweek them to make them work in a system that's set up for a 58.
Anyway, that's my 2 cents. Take it or leave it.