For 5 years I used a SM57 for miking a guitar gab. A pretty regular metal setup. After an abusive lovestory between me and my 57, it broke.
So i needed a replacement, and i wanted to test the B57. After purchasing the B57 i was pleasantly suprised. It has everything that the SM57 has, but with a slightly better feel on the construction of the mic. The tone seems to be identical with a good twist for my personal use;
As i have my cab in the open without any isolation, i needed to place the old SM57 so it was facing away from the loudest unwanted sound source. This setup will neglect almost all the natural reverb that bounces straight to the back of the mic, because of the SM57 pickup pattern.
So if you are looking for some natural reverb that bounces from the wall, or even from a reflector to your guitar recording, while still having that iconic 57 sound, this is the mic for you.