Music on Hold MP3 vs WAV which is better

If someone is deploying a server which will house 500 - 1000 extensions, plenty of system resources, which is the best way to go WAV or MP3, some people have suggested RAW but then supposedly you need to restart the server or asterisk and that you cannot interface with them in the FreePBX pages.

So whats better WAV or MP3, i have heard a lot of opinions and feelings but no real facts. so just curious bec people are saying that MP3 can crash the server or cause the service (asterisk) to stop.

I make from my MP3 a .gsm file.
Work perfect !

hmmm, GSM actually sounds better, what does everyone else say? or GSM and WAV the same?
Next question would be is whether a GSM file uploaded to the music on hold section will work? (whether it be a manual upload or through interface)

Last i noticed that when i upload a file, like a WAV the interface seems to convert it to MP3, i tried uploading a file with sample.wav and it was converted to sample.wav.mp3, really strange as to why the interface would say that i could upload either but then not preserve the format.

This whole format thing is getting pretty confusing, would just like to go with a format that i know wont bring down the server.

If any of the above can be answered it would be extrememly appreciated, thanks in advance

There is a notion that raw files are even better because that eliminates the need to decode moh files on the fly. There is a rawplayer included with asterisk along with instructions on how to convert other files (mp3) to raw. Login to the server command line and type locate rawplayer to get a path to the rawplayer README file.

I guess I should say I am familiar with version 1.2 and don’t know if the same exists in the 1.4 tree.

wav, wav, wav of sln. I hade a server come down to its knees because of two many mp3 decodings

so, agree no MP3, WAV is good, but what about GSM even better? could placing them in the music on hold folder even work? feel free to chime in, thanks