I have both, and the sound is quite different between the tapped ‘buckers and the P-90s (which is why I bought both).
Comparing them, the P90s are going to give you a tone that’s thicker in the lower midrange, less glassy on top, and have the vintage, more rounded low end you’d expect from this style of pickup; if you’re into vintage Gibsons, it’s much more like my ‘65 SG Special than previous PRS P-90 models have been. So I find it a far more authentic vintage style guitar than most P-90 stuff on the market these days.
However, with the maple top, and various PRS advances, it’s more articulate somehow, without losing that vintage thing.
I’ve posted this little comparison demo ten zillion times in threads, so forgive if you’ve heard it. The rhythm track and first solo are the Soapbar. The second solo is the humbucker version, but ignore that since I didn’t use the coil taps, and you know that sound anyway.
The amp is the DG30. I did goose the solos with an overdrive set low gain, more like a boost.
https://soundcloud.com/lschefman/messya-deux-v2