I don't know why you are replacing the brakes, were they worn beyond use? Did you inspect them or just take the word of a dealer?
I bought Chinese brakes once in an effort to prevent a particular problem with Dexter brakes, only to have the brittle magnet wires break on the first trip. I went back to Dexter and fixed the problem with some modification. If you really want to improve braking, install disc brakes.
Are you buying drums as well? No trailer drums are balanced from the factory, but I found Dexter to have better castings resulting in somewhat better balance. I find it humorous when folks claim they balance the tires and have no clue what is really happening.
If replacing wheel bearings, use Timken brand, the Chinese junk sold by eTrailer and most other places are junk.
The tongue jack can be used to partially lift the truck for easier connection of the weight distribution, so buy the heavier model.