It's a darn good mic, but if you've got US$600 to spend on a mic, you may want to consider getting a SM58 (same capsule as
the SM7) and
a KSM27. This way, you have a great deal of variety available to record vocals.
This helps, because you can record lead vocals with one mic, and backing vox with a different mic. When you do this, the backing vox naturally have a different frequency response and "space" than the lead vocals, and this makes your job of mixing much easier later. You also have more choices when recording other vocalists who might come into your studio, as far as finding the mic that's best for their voice.
The "hanging blankets" treatment sometimes sounds OK, but usually ends up deadening the treble while leaving the mids and bass unaffected, creating a sound that is simultaneously dead and boomy.
Unless you have severe noise problems in your room, you may want to investigate moving the vocal mic into a bigger room. You can aim the mic at the closet while you stand within, or you can put the mic in the closet while you stand just outside. Again, this helps to differentiate separate vocal takes, just as having separate vocal mics does.
-Hoax