I was considering getting one or two, along with some F4 boards, but then I decided it was smarter to "standardize" on one board and be able to use it for several projects.
Back when I was learning about the H747 board, I ran into the following quote.
H7 is very complex, .... I would use F7 unless the extra performance is really really required, much simpler.
If this is true of the H747, how much more so with the H755 that has two cores!
Tom's Computer Info / tom@mmto.org