I can chime in here. I bought my car new and tuned stage 2 Uni with only their DP, and an intake at 1300-ish miles. I never once had a issue with the that specific tune. I added a turbo inlet elbow and exhaust a little later on. Not sure what people claim about Uni being conservative because I was gapping all kinds of challengers. This was on a stock clutch. I then added an ACT stage 2 clutch and Mishimoto full intercooler kit and was then gapping Mustangs, Challengers, Nissan Z cars, all kinds of stuff. I went some 100k miles enjoying the tune's power/performance before going to an IS38 and trying Unitronics tune for that upgrade. I did talk with Unitronic about their IS38 file, because I was smelling fuel all the time, and their answer was that their IS38 tune would need special calibration to work with all my other mods and correct the fuel issue I was seeing. After some 2000 miles of thinking it would be ok, I gave up and switched to OS. The stage 2 Uni is quite good in my experience, and friends of mine that also have that tune. They also have never had an issue.
*I believe you can do like me and my friends, and get the supporting mods like turbo inlet elbow, a GOOD intercooler solution, intake, and enjoy the stage 2 Uni just like we have. Do keep in mind of the $ investment and in my opinion will hit a power cap/ceiling with the stage 2, but it will still be a very quick car. If you switch to OS, you open the door for future improvements and will have a tuning solution that can progress as you upgrade your car. If you know you will never upgrade again after this Uni stage 2, then I say send it. Just think about what you might want in the future. I made 333hp/389tq on Uni stage 2 and enjoyed it for a long time.
Best of luck to ya.