Ricok987,
I have slaved my SY77 to a Roland vs1680 and it works perfectly. I also, have the pc/cakewalk setup but have not really used it to slave the SY. Rather, I have used the SY77 as the master to all my pc software. My suggestion is to try both and use the one that is easiest for what you're trying to do or has the least amount of latency.
Good luck