not the best customer service evah... had a very bad experience for a rotor chainring (and I was in Germany and they are Germany-based) which took 4 months to arrive (and was in stock!).
Interesting, I've only used R2 pre-brexit and got on ok but didn't have to return anything/interact with customer services.
I basically gave up ordering anything from the German sites after Brexit. But I haven't looked into it for a while, are most of them now back to delivering to the UK?
Not a crazy bargain but you can get a pair of Centerline X CL delivered for £66.92 from
https://r2-bike.com/SRAM-Brake-Disc-Centerline-X-two-part-Rounded-Edges-160-mm-Center-Lock