We have a 27" Vizio that we take from the house and use in the living area when we are camping. It is a great size IMHO. I have not found a locking mount that I trust so we store ours on the bed covered in a blanket to keep it flopping around and getting damaged.
2012 Jayco Jay Flight 267BHS - Equal-i-zer WDH
2012 Dodge Ram 2500 Crew Cab 4x4 CTD
Me (Greg), DW & DDx2