From my experience, it is not so much the aspi drivers that have problems, but rather software looks for aspi 9x driver listings in the registry . . . when they are not found, the progs fail.
WinXP only needs two of the four files used in 9x, but it will function with all four installed on the system.
Older progs (CDRwin comes to mind) will not work on my system unless it finds all four files.
As for the 4.7x aspi series, I cannot remember where I found it (here, CDRsoft thread?), but there was a simple registry listing that was missing from 4.70 (fixed in later releases?) that was needed. After adding the registry settings, everything modern seems to work wonderfully (Nero, WinDVD, etc.)