What do you mean by "best"? The most accurate sounding? The most configurable?
I'm not nearly as knowledgeable about this stuff as the regulars here, but last I heard anything that uses Blargg's SNES sound core is the most accurate. I use the foo_gep plugin for foobar2000.
Last I heard, .vgm is crap and if you want accuracy you need make a wav sound recording using the latest KEGA Fusion emulator.
I'm not sure how true this is now. Hopefully someone better will answer.
I use the Super Nes - SPC700 Player Genesis - Hoot Player and foo_gep plugin for foobar2000. Hopefully someone better will answer. What are the best? Me too^^ See ya
Personally, I use NotsoFatso for NSFe files, nezplug++ (be sure to look for the newest version) for NSFs/GBS/etc. (it covers a lot), in_vgm (I think... I can't find a lot regarding how to play VGM files....) for VGM, and SNESAmp for SPCs. I'm sure I have a ton more, but I don't remember which ones right now. Audio Overload is reasonably popular, and does a good job. I think a lot of the codebase is pulled from MAME, but since I don't use Audio Overload, I could be wrong.
Regarding the VGM format (TL;DR verson is in the paragraph below), the format itself isn't that bad. It's a logged format (as opposed to a ripped format like the xSF (and similar) ones (PSF, USF, GSF, GBS, SID, etc.)), which is essentially a "recording" of the various signals sent to the Audio Unit of the console in question (whereas a ripped format includes the original software used to play the music) However, the problem with playback is that very few (if any) of the VGM players have the emulation "just right", so none of them sound like they do on hardware. Except, apparently, for Kega Fusion. Thus, if my understanding is correct, if you play VGM files in Kega Fusion, they should sound "just fine". However, it is possible that, due to emulation problems (which I already mentioned), when creating a VGM file (which is a logged format, thus essentially a "recording" of sorts) not all of the information is emulated properly, and thus is not logged/recorded properly. If it were a ripped format, this would be less likely to happen, because the data being used is the original data (from the ROM or whatever), as opposed to a "recording" (aka, log) of the data. Nonetheless, a ripped format can still have its faults (as seen by USF from games that were ripped numerous times to fix the bugs previous rips had).
Anyway, the "TL;DR" version is this - The VGM format itself is pretty good (a ripped format is almost certainly better, but not always), but the Genesis emulators used to play VGMs need improvement.
Anyway, sorry I can't be of more help. Hopefully someone else comes along with more information. Mouser X over and out.
Best ones for *accuracy* are anything based on Game_Music_Emu (mine, kode54's, the DeadBeef's author's.....)
Though mine is very rough around the edges and needs a lot of stuff to be up to date for the new Winamp. Doesn't help things that I also code FB2K stuff now, and I find its API and SDK more pleasant...