Yea, the funny thing is that about 90% of the save time is just doing a search in your saver/ folder. So, if you only have a handful of games, saves can be really fast. For me, saves ended up being closer to ~30 seconds. On the other side, well, it's a GBA clocked at 16MHz.So, loading is inherently going to be slow if it involves any sort of copying. Nice, authentic, slowness.
The exact limit is 49 bytes, IIRC; 8.3 names are 12 bytes for a frame of reference. I don't know if internally non-ascii characters take up more space or not, but I think I've only ever had one game which had saving problems at the 49 byte limit, and I recall shorting it only a few characters more and it started saving properly. Still, yea, it's a silly annoyance to have to manually shorten the rom and sav names.
Beyond sleephack, there's also the EZ-Flash Wiki on GBA sleep mode with the EZ4. Yea, it's a pain to manually patch games to work around a hardware bug, but I put it in the same scope as all the other patching one has to do thanks to the EZ4 long ago losing official support. As an almost aside, basically all the above complaints would be likely readily fixable (well, not the slow loading to PSRAM) if the source code to the client and loader were released. Still, for all its warts, it works really rather well.
Having said that, if you have the money, I'd almost recommend something like the GCW Zero. It too has its own warts (sticky button issues and not likely to ever reach 60FPS on all GBA games). If you've got a GB Player, though... I have to say, that's still one of the sweetest ways to play GBA games.
But playing Mother 3, through emulation its awful, specially while doing the rhythmic combos right.
