I've noticed the screen sharing quality has gone decidedly downhill since I upgraded my work and home machines to Mavericks. With Mountain Lion, connecting to my work Mac - I'd consistently have visually clear, responsive connections. Now, with adaptive quality, anytime anything moves or scrolls the visuals blur for a short period (which is annoying) - and if I change it to full quality, the responsiveness goes down the toilet. It feels more like a standard VNC session, to be honest - and standard VNC sucks.
Hopefully they'll fix this.