HI Nick
I had one briefly, and it didn't work for me as it didn't have enough grip to push a 1300kg van from the road across the slightly raised (1 inch) kerb and onto my drive. The biggest problem is it is slow, so you cannot get a good run up to a small step. This also hinders it from being helped by pushing. Once on the drive (gravel) it struggled again and just dug a hole for itself in the gravel. I went for a full mover which works a treat.
My Dad now uses the Hitchdrive to move a 1250kg van around a fairly level tarmac driveway and it works well for him, giving much more manoeuvrability with the van by himself.
I bought mine second hand off ebay and paid much less than the new price.
Hope that helps.
Cheers
David