I love the look of a curved station but have always shied away from it because of concerns about the reliability of uncoupling KDs. Uncoupling KDs is a question in itself, permanent magnets, electro-magnets, by hand, etc. that I still don't have an answer for.
I have found that the new whisker and scale head KDs are far superior in performance to the old No. 5s, however because they are so good, with 4 wheeled stock they can false uncouple when moving slowly over permanent magnet uncouplers. This is a big issue with steel axles on light 4 wheeled stock.
I only put permanent uncouplers on stub ended sidings so it's not that big an issue and can be overcome somewhat by adding weight to the wagons. This suits me as I like my loads to be heavy to give the challenge of getting up the grades with bank locos.
I am hoping to build Cassilis station yard with handlaid points as per Bylong station so curving might be the way to go, perhaps a nice broad curve will still allow the KDs to couple and uncouple, I must do some trials.