In September, I purchased the D10 R2 wanting the ramping UI. However, I ended up with the SP version which is the 3-level version. (The box did state "SP" for the model which is the 3-level version.) I didn't know at the time that there were two versions. Initially, I was disappointed as I wanted the ramping light - just thought it was very cool - and thought about giving it away for Christmas.
Well, I also purchased a Nitecore D20 as a gift. After playing around with the ramping UI of the D20, I realized that as novel as the ramping is, I find the 3 level UI more convenient. You can "tap" the ramping UI to go from Low to High and vice-a-versa, but having the medium available much more quickly is more convenient than ramping.
I may still get the ramping UI (probably the EX10) just because is different than my other lights but from a usability standpoint, I think the 3-level UI is better.
BTW - if you haven't already, the D10 on 14500 is pretty darn bright. But then again, I suppose that can be said for any 1xAA that can handle 14500
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