Ah, I was using C but I didn't realized needed to strip the binary, after doing that it comes down to 39k which is smaller than the Microsoft equivalent so you're right, it does seem to be using dynamic linking :(
Is it possible to do that with the latest versions (i.e. linking to their CRT instead of MSVCRT.DLL), or are they incapable of doing it for some odd reason? These are the options I used:
/MD /O1 /Os /link /align:4096 /filealign:512 /merge:.rdata=.text /merge:.data=.text /section:.text,EWR