I recently bought an h7. To be honest it's a little more of a learning curve than expected.
A lot of more basic code doesn't transfer over directly, and that hurts it.
I also have a few teensy 3.5 4.1 etc. For me most of my work is in control systems, and the dual processor/integrated features seemed really promising. But if I can't do the more basic stuff easily, I don't expect that taking advantage of more advanced features will be likely.
I will keep trying with it, but it seems like the h7 is going to sink. Price is so high that not a lot of people are getting on board to work through the issues. The advertisement is for easy to implement professional grade solutions. But so far, some of the issues aren't even "easy" or "hard" they're flat out mysteries.
Other platforms exist that cost less and have more streamlined integration.