The SM7b is a nice large-diaphragm dynamic mic, designed mainly for vocals. It is a vastly superior mic compared to the Perception line of Chinese mics, but it's not a "do-all" mic. Another alternative to the Shure would be a Sennheiser MD421, which does well on vocals, and is great on percussion and bass instruments. For vocals, be sure to use a windscreen to minimize 'pops'. Similar price as the SM7b, but you get what you pays for, if you know what I mean. Another mic to consider would be the Heil PR40. A tad bit less $ than the other dynamics, mine works well for voices and low end instruments, percussion, pretty much anything you throw at it, and the pattern is tighter so that it picks up less of the room. This is good when you have a less-than-optimum acoustical environment. In fact, I have 2 of these. Something to consider, too, is the build quality of these mics. The AKG Perception line is their bottom-of the-line, and their capsule design tends to make them sound "sizzly" on the top end. Plus, they have a cheap "feel" to them (IMHO). The other 3 models listed are better-grade models from highly-respected manufacturers. Solidly built, they will remain desireable many years down the road.

I've heard a few samples of the MD421 and didn't like it too much (it sounded a bit too "crunchy"... dunno how else to describe it), so I'm probably not going to get one of those. The Heil PR40 is not available here (although I might order from the US anyways because the SM7B costs almost twice as much here...)