I have pulled 1/4 ton military trailers over the Rubicon for over twenty years. Some loads have been heavy (repair parts for the mechanics area, lumber, concrete, blocks of ice, etc) and some loads have been rather light (less than 500 lbs). I have had a few times that i wish it had brakes (although on the miltary, you can go out and set the parking brake and then "drag" your trailer down obsticles).
For the most part, it has been fine without them. I found it hard to want to pull off the military axles when I have built trailers because the parking brakes are very handy when you unhook in camp (a must with an RTT on there!). I find that pulling them up hill is much worse than pulling/getting pushed downhill.
I see all of the fellas here with awesome builds, but the first thing they want to do is ditch the military axle for some thing with electric brakes. I would bet that the e brake would get more use and be handier than electric brakes to help stop the trailer.]
My only real complaint has been with the pintle hitch. They are great for pulling on a road, and articulate very well, but can be very noisey and do damage from the push/pull effect when there is even a little play in the hitch. I love the Max Coupler type of hitching system, and think that I will be changing over my two pintle hitch trailers to that soon.
I have not looked into a ste of brakes with both electric brakes and an e brake system, but that would be awesome. Maybe someone whio has done this conversion can chime in about it??