The best monitor under 1500

Spendor 3/5r2!

Since this is RV, why don't you go for the Pioneer SP-BS22-LR and save some?
With experience I can say that if you keep them between 1-2 feet from the rear wall you will get pretty tight bass. Move them 4 feet from rear wall and the bass goes bye bye. But the overall experience with this speaker has been amazing. So highly recommended.

KEF 50 is a great rock speaker, but IMHO way too forward for Classical .

KEF ls 50 is a nice choice for an RV. It has limitations with larger rooms from what I have heard, but a very nice and compact package for many applications. Am RV sounds perfect. They do like power and current though so expect a significant variation in performance based on amp used.

What about something like a Thiel Powerpoint? Completely out of the way and great sound.