Wheres the seat to sit on? 
I do like there wheels on them however, at the range I shoot on is sandy and hence I am forced to use wider wheels (they are wheel barrow wheels) it was cheaper to buy a hand trolley for 25.00 just for the wheels than to buy them individually at $30+ each - crazy.
For soft, sandy, or tough ground I would go with the garden wagons. The wagons with flotation tires, wire mesh floor and sides, and that pull. I always find that pulling is easier than pushing, and those wagons can carry the gear for a full squad, have a table for cleaning and loading magazines, and a simple plank can be placed on it of a seat if you do not wish to carry bag chairs along.
The down side to these wagons is that you need a pick up or suv to haul them (too big for a car), and they are slightly heavy to load and unload.