Just out of curiosity, am I right in thinking that the MorphOS implementation of WarpOS compatibility is more stable/reliable/better designed than WarpOS on OS3.x?
The last version of WarpOS contains some bugs that were never fixed. And I guess it's safe to say that they never will be :-)
Anyway, WOS emulation in MorphOS doesn't have (all) the said bugs, therefore some WOS programs/games (glquake at least, iirc) work on MorphOS when they fail on AOS3.x+WOS.
Also, many games/programs run faster, becouse there's no need to switch between 68k & PPC and some system functions have been rewritten as PPC native.
It's also worth pointing out that BPPC version of WOS is more buggy than CSPPC version (I think that glquake worked on csppc)
But in any case, it doesn't matter which one is better (I'd say PowerUP), but WarpOS definitely has more software (so I ended up using it anyway) - and you can run most PowerUP software with emulation anyway.
Also, both MorphOS and AmigaOS4 exes use elf format like PowerUP does (you know, "the monster" :-D)