If you step record you should really should quantize with a groove template or with some sort of humanization treatment that takes some of the mechanical preciseness out. Personally I alway prefer to record sequences in realtime and then quantize to just a percentage rather than put everything precisely on time. That way I can keep some of my original feel but correct the occasional note that was starting to slide a little too far off time. If the track sounds natural without quantizing I will leave it alone and perhaps tweak the odd note by hand. I just decide on a track by track basis.
Because I play guitar as well, playing a realtime guitar track over a tight quantized performance tends to make the overall sound seem natural. You could do the same with just keyboard by playing one of the prominent parts ( pick one that you are able to play comfortably and leave the more difficult lines to the computer ) in realtime over a sequenced backing and that would be enough to impart a human feel to the track.
[This message has been edited by Nigel (edited 01-19-2005).]