Sad that they discontinue the old model with ramping (from their website), the new UI in SP model are considered "executive"-mode by some as all modes are preset. The hidden strobe and SOS mode as well as lock-out mode is a nice touch, but having to compare both older and newer SP model side-by-side, I've chosen to get the XP-E D10 with ramping UI. It also appears that the XP-E version of the ramping model is slightly brighter when comparing.
I've had a chance to compare all 3, XP-E D10 with ramping UI, XP-E D10 SP normal, and XP-E D10 SP Camo. The Camo version is nice with tritium slot at the back, there is also a special edition that comes with tritium pre-installed. The anodizing on these Camo version is also nicer (smoother and more evenly done). If not due to the nicer tint, brightness and smoother operation, I would have gone with the Camo version... :shrug:
FWIW, the piston tube of these new SP model is different from the old, they change the position of the oring, instead of having it at the main piston body, now the oring is located at the button side, I agree that this may provide better waterproofing, but it's not as smooth. Btw, these piston tubes are not interchangeable (between old and SP model). :sigh: