My .02 cents
lockable box - is a must it its not enclosed
Surge brakes- personal preference
WINCH- I don't have one, but I will shortly.
lots of anchor points-(e-track is great) all of my friends use it. I have had 20 different cars and motorcycles on mine, never enough tie-down choices with 4 d rings
spend a little more up front- I agree with jwilly, , you'll be happier in the end
Jason