My only SP-only unit is the Sharp MT831, but it's my favourite unit of all the ones I own (including MDLP units). I've never really used MDLP anyway, so the 831 feels like a fully functional unit.
What I really like about it are the details - I think it was a pioneer for MD units. The charging cradle is really well thought out, allowing operation while charging the battery. It has features, which may have been the first time implemented on an MD unit(not sure about that), such as a defeatable beep and backlight on the remote, as well as defeatable features like auto play.
The other thing that I like about the unit is the accessories. The remote is easy to operate with the jog dials, which also come in handy for titling discs. The AA battery pack is also nice and solid, unlike the ones on units from other manufacturers.
Of course, there's the meaty 10mWx2 amp, great sound quality, simple layout, solid craftsmanship, and stunning looks. Combine all that, and you've got one solid MD player.
I don't use the unit much for recording, but if I did, I'm sure I could write a couple more pages on how well it performs at that as well.