I went thru all this a couple years ago. From what I understand, the 2000 and 2001 had a little higher oil pressure than the SP2's. The blue filter was made specifically for the SP1 specs, but it wasn't that economical, so Honda determined the more common black filter used on the SP2's, and many other Honda's, was within the spec range for the SP1. So they discontinued the blue filter. I don't know what the exact differences are.
Someone here, maybe Madbuyer, suggested the Honda warranties it's filters against any damage to your engine. Non of the aftermarket filters do that.