Yeah, the Wankel is cool but not without issues.
A friend had an RX-8 and it’s engine wore out in less than 100,000 miles.
I have owned two RX-7’s decades apart from the ownership of each one. I sold my last 1979 RX-7 about 14 months ago.
The Wankel engine is a piston-less engine, with three rotors (think triangular) that revolve like the hands of a clock. There are several reasons why Wankel engines never caught on. The reasons are:
American drivers tended to practice American car maintenance practices to this engine, which is a mistake.
Wankel engine drink a lot of oil. In the original 1979 Mazda RX-7, I believe that it said in the owners manual that you should add a quart of oil every 1,000 miles.
Also, the wear on the Apex seals over time causes poor performance.
These cars were not environmentally friendly on emissions.
RX-7’s with 5 speed manual transmissions were very fun the drive. I especially liked the fact that these cars didn’t hit the redline on the tachometer until 7000 rpm. It was a quick and responsive sports car.