Internals are the same basic design found in all Microtech D/A OTFs.
The machining on the Troodon handle is probably a little more expensive, but probably not enough to justify the price difference. Everthing else about the Troodon is smaller, so there's less material cost. I would guess the reason for the cost difference is either volume (lower volume sales make any item more expensive) or marketing (charging more for style, etc.).
I much prefer the Troodon due to the size and weight, plus the SE blade on the Troodon is much nicer than the SE blade on the Ultratech. The only thing I really like better about the Ultratech (besides its price) is the thicker blade.