I've used yaris and K20 coils in my sr20 when trying to source a misfire which finally wasn't coming from the coil packs.
To be honest i didnt see any difference in perfrormance. I kept the K20 on.
As an upgrade its super easy if you have a stand alone ecu . You just bypass the ignitor, and change the pinout. Everything can be found online , dwell times etc
Installation is easy. The Yaris coils i think one of them only needed some triming.
The k20 sits a little taller and you need some open spacer to fil the gap between the coil and valve cover.
https://imgur.com/a/VI2OE6q