It will run fine on Mavericks. I have CS 5/Mavericks running on my 2007 iMac. Little slow, but that is because of the iMac, nothing else. I am also running both CS 5 & CS 6/Mavericks on late 2012 iMac's with no issues. Pretty quick on the 2012 iMac's with Fusion Drive and other with SSD.
Both CS are the Master Collection and have not had a single issue with any of the programs.
I've been running PS/CS5, along with AI and Id, on Mavericks for several months. It's stable and runs about the same speed under Mavericks as it did under Snow Leopard on the same MacPro (late 2009, dual-quad core, 16gb RAM).
The only issue I've seen has been with cursors. The tool cursors don't accurately show the actual size (Brush, Paint, ...) and occasionally the cursor will vanish briefly when the machine gets a tad busy in the background (Panning across a 2gb PSB file with 10-20 partially masked adjustment layers to render at %50).
Still Running CS5 on both Snow Leopard and Mountain Lion with no problems. Tried Mavericks but went back to Mountain Lion. There is an interface in either Snow Leopard or Mountain Lion that I need in my workflow that is no longer available in Mavericks.