I am a first-year PhD student interested in working with a professor at my university. I have had two nice meetings with him and liked the project ideas we discussed.
But a student told me that he thought the professor's work was derivative and mostly hyped. I asked my academic advisor (a professor who suggests courses to take, answers questions, etc.), who agreed. The thing that stood out from his answer was: "Yeah. Professors talk about other professors, and ..." Which suggested to me that this was not a solitary opinion. The advisor's point was, without being primed, essentially the same as the other student's: the work often seemed like a rebranding and slight modification of other people's work. FWIW, my academic advisor is the research advisor of the student who first warned me. I didn't tell them what they each said, but I can assume they have talked.
Anyway, now I am wary. How can I better judge for myself, given that I am too junior to honestly know if the work is derivative. The professor is quite young but has been publishing in the top journals/conferences in the field.