Oris UK Sevice Centre.
Bit it tongue in cheek, but after having had a bad experience with a third party servicing a Breitling, I always accept the slight premium and go for the original manufacturer.
My worst experience ever...I once took a watch to The Watch Lab for a service, they charged £280. I later found out that they just sent it straight to the manufacturer who charged them £160. This info was kindly volunteered to me by the manufacturer who checked their records against the watch. I felt like a right mug.
The best independent servicing I’ve ever had done was by Paul (walkerwek1958) on this forum. I highly regard his work.