As Bob says, UTD is the brainchild of Andrew Georgitsis, with whom I have done some training. The agency is only about a year old, which is why the instructor cadre is currently small. I'm sure it will both grow and slowly, as the process for crossing over an instructor is much easier than GUE's (you don't have to start at the Fundies level), but the intent is very strong to keep quality high.
As said, it is very DIR-flavored training, with the same basic concepts of standardized gases, standardized equipment, strong emphasis on team, and high standards for skills. Andrew heavily emphasizes "thinking divers" -- small, non-repeated errors in technique aren't penalized as heavily as failure to analyze problems and take appropriate steps to solve them. (In other words, you aren't going to fail UTD classes if you're briefly 20 degrees out of trim in midwater.) There are some small differences in equipment configuration, but UTD is also more tolerant of small deviations (long hose under or over, for example). 25/25 is the deep recreational gas, and decompression is pure Ratio Deco.
There are a number of things I think Andrew is doing VERY right with the new agency. Many of the online classrooms are excellent, and giving students the ability to work through them before class makes the academic time much more efficient. There is also a strong emphasis on community (which is one of the delights of DIR diving for me, anyway). I like the way the curriculum is broken up, even if some of the divisions have some odd consequences. I just finished UTD Technical Diver 1, which is like the first half of GUE T1, and was perfect for me. I think a lot of people find the jump from Fundies to T1 daunting (I did, and I've talked to others) and UTD T1 is a great halfway measure, introducing some small amounts of decompression and all the ideas that go along with diving under a virtual overhead.
The recreational curriculum is also excellent (and I did Rec 2 and Rec 3 with Joe Talavera and Andrew, respectively, before UTD was formed). If you want high quality training to become a self-sufficient and skilled member of a diving team for any recreational diving, through recreational helium use, it's a superb pathway. GUE's recent release of their recreational sequence is almost identical, which I suspect is no coincidence
It is my personal opinion that GUE is still a better route to cave diving. But Andrew's primary love and strength, to me, is technical diving, and it shows.