I'm not sure how you would go, seeing that the SM 57 is not a stereo microphone. Most likely, you'll end up recording in mono on one channel only. Not necessarily a problem: the actual recording will possibly be clearer and better defined, due to absence of multi-path reflections.
The SM 57 is a close-range microphone. You need to have the drum within a foot or so of the microphone for it to perform well. So, as an ensemble microphone, I suspect that it won't work well at all. As a close-range djembe microphone, it's a good choice.
In terms of being "better" than the built-in microphones, I have my doubts. Certainly, as a workshop general-purpose microphone, where you record sessions and such, I would expect it to perform worse.
One issue with the PCM M-10 built-in microphones is that they are omnidirectional, so the stereo imaging isn't all that great. If you want to improve on that, the Sony MS957
is a reasonable choice at a reasonable price. A slightly cheaper option is the Sony MS907
. Like the MS957, it should also deliver better imaging than the PCM M-10 built-in microphones.
For something more up-market, check out the MXL V67Q
and the Audio Technica AT8022
. If you want to go really up-market, try the Shure VP88
. And if you happen to completely lose your mind, at $5,550.00, the Schoeps CMXY 4V
is an excellent choice