Here is my review of
the AT2020:
http://mojopie.ipbhost.com/index.php?automodule=blog&blogid=1&cmd=showentry&eid=87
We did discuss the merits of all the mics referenced in the review.
Steve B. (songwriter/engineer I work with) thought the B1 sort of suited toms. I sort of hear it more as a percussion mic the more I use it. I no longer use it on acoustic guitars at all. But, I do still use it on amps.
We liked the SM58 for the proximity effect. If you want proximity, then grab an SM58. If you have a strident singer, then grab an SM58.
We liked the Beyerdynamic Soundstar MKII. It has no real proximity effect. I see why Harvey Gerst recommends these for VO. It is a brighter dynamic mic.
We liked the AT4040. This is a real special mic. I think it's the best price/value mic on the planet right now.
We also pulled at a Blue Baby Bottle for a tad bit. This is a good VO mic. I don't think it gets enough respect. It sounded boxy in the room. Steve B. has an isolation closet and it sounds wonderful there.
Of the mics we used for comparison, the AT2020 is most like Beyerdynamic Soundstar MKII. Like the Beyer mic, the AT2020 is a decent choice for vocals and spoken word. On instruments the AT2020 is about the functional equivalent of the Studio Projects B1. The AT2020 is a different flavor than the B1 but it can cover a lot of instrument/amp situations. If you've got a B1, then the AT2020 would give you a different flavor plus the added ability to cover vocal duties.