Full Disclosure, I am a coding bootcamp Campus Director.
I can't speak for the UC Berkeley program, but we do have another Trilogy Education Services program run through the University of Texas here in Houston. I believe the program (at least, the web dev one) is identical.
I've met with several students of these Trilogy courses and attended their first graduation event here. By all accounts, the program is solid. However, I would always recommend getting specific info on who would be teaching your cohort since that is the most important point to consider for any course.
I would suggest going on LinkedIn and doing a search for people who have done the course. Most of these people will also have public portfolios or repos that should include some contact info. Here are a bunch of them https://www.linkedin.com/search/results/index/?keywords=berk...