Probably not much help but I've had the tall storage cabinet for around 18 years and it seems to be wearing well. The colours might have dulled a little but it still watertight and the doors haven't warped or shifted like the wooden ones on the 'proper' shed that's half it's age.
The taller one I have fixed to posts so it can't blow over the other is too heavy...both do the job well...better than wood that needs treating every year..
The reason I ask your views,I've had one for 4 years 8x6, the condensation is terrible, I have fitted 4 extra vents in the shed & it still persists, I did contact Keter & said that I had to throw quite a lot of tools away because of rust, about £80 worth ( Honest) I wish that I had chosen a wooden shed, thanks for your views, ( Anyone want to bye a Plastic Shed)