Thanks for the replies so far!
I would use the mic with the pre-amps from a RME Fireface UC or an old allen & heath mix.
The portability of the fieldrecorder is def a big plus, but I wouldn’t shy away from having a long cable for the mic and record from a distant.
The field recorder probably has two SDC mics in a XY configuration for capturing stereo sounds. Therefore, all the usual caveats of el cheapo SDC apply, overly bright high frequency response (recording tavlas etc will rip your ears off!), somewhat naff off-axis sound, and a sure capture of any unwanted noises like jackets rustling etc…
An SM57 OTOH, will perhaps offer a slightly mellower tone, and will pretty much only capture sound from its frontal area. You need to get this one close micd for most applications. And you need a healthy mic pre with enough clean gain to drive it (you can get a cloudlifter for adding ~23dB of gain though, just be mindful of the cabling!).
That’s my concern about the two.
As mentioned above I have decent pre-amps at hand. I could also use the one from a Motu 828 MK2 which I only uses as an ADAT-expension for the RME. So enough options here
Many insights which I didn’t think about. I am not a guitar guy, so thanks @reeloy for the hint.
Funny how you guys pick the jabbering-thing