Originally posted by Skewer
As far as the NES Recreations of the SMB3 SFX's go, you'll find that rather difficult as SFX require quite a bit of ARAM
Depends on how you go about it. A modern approach would be straight up "sampling" the sound effects which will eat ARAM. If you do it more like an NES, pitching square waves and what-not, then you should consume even less than SMW's default or #optimized.
From working with custom sounds I can't say the individual sound effects [or samples] are costly; it's a matter of how many you load versus actually need for a piece of music, that is loading superfluous samples you will begin to see the problems. Even then the Echo Buffer can easily be the most expensive use of ARAM if you choose to use it.