I didn't have any problems with Maverick when I upgraded my MBA.
However, when I bought the new MBPr (which came with Maverick), I could not add my gmail account into the default Mail application in the MBPr. However, my gmail is working fine on the default Mail application on my MBA (which has been upgraded to Maverick) though.
Anyone has this problem that you cannot add gmail into the default Mail application under Maverick? Very frustrating .....