We've just had a long thread that seems to indicate that the V57M is a little different than everything else but close to a 2001 in the body of a V67. Or maybe it is a 1006.
The V63 I am fairly confident is the same as the 1006 as the specs are the same and both come in battery and phantom powered versions and are the only MXL mics to do so.
The 990 is a little different than the others. It is a small diameter condenser in a side-address casing. Electrically it is similar to the well regarded 603, but like all small diameter condensers its reputation is for being pushed hard on instrumentals rather than vocal.
At the price that it is being sold at the V57M is undoubtedly a bargain, but nearly everybody seems to have a MXL mic that they actually like better even if it costs more. Some folks really prefer the V67 and others really prefer the 2003, also known as V93M.