It is kind of an odd pairing. I can't answer the question for you about whether or not you value a D100 + lens more than a sd633.
But if you leave the lens out of it and consider only the recorders, the two comments I have are...
Do you want DSD? If not, then what does the D100 give you that your R26 doesn't already give you?
Then if you comps the D100 against the 633, there's really no comparison. The SD633 hands down is the one to get based on features, channels, aesthetics, fun, and on and on. It's alot of money, but I recently picked up a 744 and I've never been more pleased with a purchase. I'm pretty sure the 633 would have thrilled me even more, though of course the 7xx series lights in the dark are mesmerizing.