The most important thing is to choose coarse threads, then it will probably never come loose. Cut in really well the screw I'm using now had coarser threads than a French screw of the same diameter.
How much can the hose withstand? When washing the car, we go over a gravel road with lots of stones and gravel. Can it be damaged when cars drive over the hose?
Planning to install a similar one but in a lightweight concrete wall. I'm considering whether to buy special lightweight concrete plugs or if the included ones will work. It will bear the weight of the hose reel and water, and then you will pull on the actual water hose.