RS80s are great wheels. But if you bend them or prang a pothole, or when the rims wear out, you’ll have to buy new wheels because the cost of a new rim is pretty close to the cost of a new wheel, and often it’s higher if you factor in paying someone else to rebuild the wheel for you.
Hand-built wheels may be a few grams heavier (it’s easy to sell people stuff when they only care about its weight), but they can be much more durable, easier to re-true and you have a lot more options in case they get damaged or wear out.
For £300 I could build a pair of Ultegra hubs on DT RR415 rims with Sapim Race double-butted spokes. They’d be about 1700g for the pair without QRs and rim tape and they’d come with a lifetime warranty. For just under £400 I’d build them with Sapim CX-Ray spokes (probably the best in the world) and the build would be under 1600g and a lot more durable than the RS80s.
Edit – just spotted you mentioned the 23mm rims. I like Velocity A23s as well at the moment, slightly heavier but cheaper than the RR415s.