This pretty much sums it up for me. I like carbon rims. How they look and sound is very much a part of it. I think there is something about ride feel, but I can't say for sure that is real. And absolutely they just stay true.

There are known aero gains with modern shapes and medium to deep (> 30 mm), and generally less weight. These aren't huge, but if you want to get that last bit of performance...

If the money is a stretch, I would spend it elsewhere as I don't think you'll notice some huge difference other than the sound. Carbon rims sound cool. But if you have the money and just like the look and general idea, go for it.