I do not use the sequencer for recording, I use an old Atari 1040ST computer with Cubase for that. (I started to use Cubase on my PC as well)
According to the information I got from other XP sequencer users, it's a relatively easy to learn one, especially the numberious seq-keys and the big display are a big step forward in comparation to former onboard sequencers.
I still find it too complicated, while using Cubase or other programs you don't have to start all over if you start working with another keyboard.
I only use the sequencer for playback, for it can handle GM files (General MIDI).