The popularity of this mic in broadcast studios is a testament to the clarity of its vocal reproduction. Whilst sometimes used on guitar cabinets, it is primarily considered a vocal microphone.
On male vocalists, especially those with a slightly deeper than average voice, it is capable of creating recordings equal to microphones 3x its price.
Being a dynamic mic, it is more important that usual to find a decently matched preamp with plenty of gain. For those on a budget, the Golden Age Projects Pre73 seems to add a nice rich character to the SM7b. A preamp with at a minimum of +60db gain is required.
For those with a less than ideal sounding room, the fact that it is a unidirectional dynamic mic will focus the recording directly on the source and ignore unwanted room noises.
For the price, it is one of the best value microphones on the market.
*Edit: To explain the 7/10 for "ease of use", I marked it down a few points for its gain requirements: there are a number of preamps or interfaces with built in preamps on the market that don't provide the adequate amount of gain making it a little less flexible that other microphones.
So many knobs.