Best mic for home setup. SM58, SM57 or other?

I'm still rounding out my home/bedroom studio setup and I need to choose a basic inexpensive mic that is reliable and will produce reasonable results in a home setup. The room is a standard second bedroom size on the second floor, carpeted, with one dual pane window with blinds and a double-closet (roughly 8 x 10 i'm guessing) and will not be attempting to make an iso booth or slap any Auralex on the walls (at least in the near term future).

I will be recording mainly vocals (lead and backing) and possibly an acoustic guitar and a djembe (those will be dropped back in any mix as i'm neither a guitar player or a drummer!). Possibly also a harmonica which would be more prominent than the guitar or djembe would be. I'm looking for a mic that will add a little warmth without coloring the sound too much.

The old favorite SM58 is the first choice that came to mind, although I also thought about the SM57. Given the above factors, what mic would you choose (in the price range of the SM58)?

P.S. I know I would get better mic recording and overall monitoring results by relocating my studio downstairs (actually my wife's suggestion), building an iso booth and using Auralex - those tasks are on my future to-do list.

If you plan on making a good quality acoustic guitar recording then a condenser mic (like the one bitflipper mentioned) is a good investment. In fact, if you plan on doing much recording of anything then you will want to have one around.

Having said that, my first mic was the SM58 and I still prefer to record vocals on this mic going through a good preamp, even though it is a dynamic mic. This is because my room sounds awful (and a condenser is really sensitive) and also because I haven't been willing to shell out for a better quality condenser since I want to be able to try it first!

The SM57 will also be useful for almost anything, especially drums. If you have to choose between 57 and 58, I would go for the 57 just for better all-round usability.

Cheers

The SM57/8 also has limited high-frequency response, falling off at about 15KHz, IIRC. Not a problem for rock vocals, but it loses the sparkle you expect from a fresh set of strings on an acoustic guitar.

This is why we tend to accumulate a collection of microphones over time - different mics for different applications. A large-diaphragm condenser for vocals, small-diaphragm condenser for acoustic guitar - and everybody has at least one SM57 in their collection. But for your situation, an LDC is the way to go if you can only afford one microphone right now.

The high-frequency response is an important consideration. A decent condenser will go to at least 20-25KHz. The additional upper frequencies are very noticeable for many instruments and voices.

The CAD M177, under $200, is a decent LDC that also offers the ability to adjust its pattern, from figure-8 through omni. Pretty cool feature.

I sometimes record a track with more than one mike, not for a stereo track but to make two different mono tracks, from which I can choose the one I like the best. No one's paying for my time, so I can afford to experiment. What I've learned so far:

(1) The same instrument usually sounds noticeably different when recorded by different mikes.
(2) The usual rules of thumb about which mikes work best for what instruments often apply.
(3) The usual rules of thumb are also often wrong.
(4) Which track is "better" is often a matter of its intended place in the mix or other subjective factors.

If you have a reasonably good LDC plus an SM57, you'd be pretty well set. I'd feel like a one-armed person without both.