The SC-55 MK2 is a general midi device, the MT-32 uses it's own standard.
Dos games after +/- 1992 started to use GM midi instead of the MT-32.
For Amiga games I think the SC-55 is not very useful. But you can init the SC-55 into MT-32 mode. It's not fully compatible (you can not send your own sounds to the device) but in most games I tried it will do a good job. It sound's more bright then the MT-32. Most of the time, I put the SC-55 into MT-32 mode and let it play along with the MT-32 it sound really good.