Again... Thanks for your responses.
Ok. A few things.
First, I'm not sure where this comes from... but I live in NYC not the UK.
Second. I did a bit of research on the MD421 and it seems like a great mic. But what I'm seeing is
the MD421 II .... Is that the same mic as your talking about or is there an original MD421 that I should look for?
Could this mic be used on a bass drum in addition to being able to be used on bass and guitar cabinets like you've mentioned? Would I be right in saying that these iare somewhat comparable to the EV RM20 in terms of applications? Or are they completely different animals? Ack.. I wish I could buy them both.
Hmm... I really think I need to up my budget at least to $1500 or so.

That said, how does cabinet look:
my current mics: AT4033, SM58, ATM41a
and adding these: AT4040, MD421, SM57, and a pair of Studio Project C4's...
Good choices for a balanced cabinet?
Sorry for the continued questions... The more suggestions I get from you guys, the more research I'm doing, and the more frustrated I'm getting. I hope not to turn into a "gear slut" but whatever. I'm sure the guy I meet someday won't complain.

Although admittingly, the image of a chic setting up a vocal up in a pair of Manolo Blahnik's is rather humorous.
Cheers!
Samantha