Lorna 4 Great product - comes with 2 sets of axel pins for different width wheel-cases and the wheels run smoothly.As other have said, the most difficult part is removing the old wheels. For the first one, we used a power drill but the plastic wheel casing began to melt and become misshapen. For this reason, we continued with a hand hacksaw. It took a long time - about an hour to saw through all 4 wheels.However, it was worth the effort as the new wheels were easy to attach and run smoothly. It is also CONSIDERABLY cheaper than asking the manufacturer to replace them.I can't comment on durability as I've only just changed the wheels.