Captain-
Why dump your Mac with MOTU DP to get a PC????

Unfortunately you probably already know that DP isn't available on PC.

How about checking out the latest version (version 9) of Cakewalk Pro Audio if you were already using it in an earlier version. This seems to have become a very mature sequencing program over the last couple of years.

I use Logic and let me tell you that it is deep and very flexible.

The same goes for Cubase VST.

If you only want to do midi sequencing, then ditch the high end versions of the above programs and get the lower cheaper versions which still contain most of the midi functions.