I managed to find one one of these accelerators recently (thanks amigadave!), already knowing the "achilles' heel" being its inability to automount partitions other than FFS (what's in ROM).
Using Doobrey's tools to create a ROM with SFS, and Thor's mumaprom to mirror the test.rom, I was quite pleased when the SFS partition showed up on the desktop, ready for formatting. This basically means you can burn your own custom ROM, and voila... automounted SFS boot partition, and no mountlists for the others.
Unfortunately, there's no way to similarly use PFS3 (my favorite filesystem, which is also 40kB smaller than SFS) since for some reason Remus won't add it to the build list ("resident not found" error) and I don't have the required skillz to figure it out. :p
