i thought i'd pulled a muscle in my back last january but by august i was at the point where i couldn't stretch anymore. This was from using the freedom trolley. Mark 1 version. I used to use my thigh to lift it.
I wasted my time seeing an nhs physio in october and then went and had a massage who then told me that i had a raised hip from lifting heavy weight continuously. The only weight i lifted was the trolley.
I have been using van mount since and i am seeing less and less pain down my left side so i can stretch again now.
Using a trolley as a van mount is a good idea but if you buy a freedom trolley or whatever type of trolley eventually, go for the lightest one. In freedoms case get a mark2 rather than the original. There is a big difference in weight between the mark 1 and Mark 2.
Regardless of what anyone says, i would always recommend a trolley as a handy piece of kit. If you get a van, all you need is a tank, submersible pump and hose and the trolley becomes the van mount.