They have different problems than piston engines. One thing to be aware of is that they all use oil, just a bit, by design.

When the rings wear on a piston engine, you lose compression, and the engine slowly deteriorates to the point where you know a rebuild is necessary. The Wankel engine wears its rotor seals, but this does not generally cause a loss of compression. Rather, when the seal gets thin enough, it can suddenly snag on a port with absolutely no warning.

I wouldn't say that they last longer, but I would say that until a rebuild is mandated, the engine's power won't diminish.

I'd be most afraid of what was necessary to get these modern Wankels to pass the EPA's scrutiny. Perhaps they're just cleaner than the old models.