I need to record female vox and I need a good microphone to capture a silky intimate vocal. I also need a microphone that will serve well with an SM57 when micing a guitar amp.

Has anyone used the Nady RSM-4 or RSM-2?
What are other good alternatives in the pricerange?

Budget : $300 USD

To Save Your Time:
I have a vtb-1 preamp.
I know ribbon mics are fragile.

If you want something dark the Nady will do the trick. I have an RSM-2 and use it for lots of things. Room mike, Amps, strings, but I wouldn't call it a "go to" vocal mic however. With the studio projects pre you are going to need alot of gain. With your budget I might think twice about why I need a ribbon? What style of music will you record? Could a good dynamic like an RE20 or SM7 get the job done? Those both need a lot of gain but have a better track record with vocals. You could get either of them for that budget.

I'm sure you know about the whole Shinybox/Nady ribbon thing. Same mic, different customer service.

I own the RSM-2 and an unbranded version of the RSM-4. I like the RSM-2 on my own voice (male baritone/bass), but haven't used it on a female vocal yet. It also has a nice mellow sound on guitar amps. To get rid of some of the "darkness," I think it helps to remove some of the layers of mesh covering the ribbon element -- they really didn't want you to damage it, so there are several layers of thick nylon-ish fabric, in addition to wire mesh, surrounding the ribbon. The RSM-4 is new to my collection and so far I've only used it as a drum overhead and on guitar amp, where it performed admirably on both tasks. I'll try to track some vocals with it this weekend and post my thoughts.

That would be amazing.

For $165 my shiny box 23 (stock version) has worked wonders on my wifes voice. Back side of the mic being a little bit brighter then the front side.

So, I did a little tracking with my Alctron HRM-15 (same as Nady RSM-4). Recorded myself doing a parody based on Neil Young's "Harvest." I used the ribbon for a mono drum overhead, on acoustic guitar, and on vocals. All tracking was through the M-Audio DMP3 preamp into a Delta 66 card.

Overall, the mic did a respectable job, but didn't blow me away. Somewhat midrangey. The two sides offer differing tonal variations, though (since my mic is unlabled) I can't really tell you which is the "front" or "back," so I just used the side that sounded best to me at the time. The overhead sounded pretty good. Vocals were just o.k. Guitar sounded kind of honky -- but I didn't take much time with placement, so it could have been just that.

Anyway, it's probably a useful mic to have around, but I wouldn't want to use it for everything.