I had one from Specialised a few years ago and it was very well made and fitted perfectly.
But as for easy to fit........(this would apply to most similar covers0. In anything other than flat calm conditions quite a problem, requiring two people. First you may have to remove TV antenna. and remove or pad cowl of heater exhaust pipe Then pad with bits of foam any sharp edges e.g. where strips of metal covering the roof to end panels come to the edge of the van. Quite difficult to make these stick in a way that survives pulling the cover across them. Then laying out the cover, arming each person with a broom for lifting the cover from the inside high enough to go over the front of he van, Then a synchronised slow march to the rear of the van hoping the cover does not catch on anything or that the wind doesn't blow it off line or that arms do not get cramp etc. etc.
Then you need to pass the straps undeerneath the van and tighten them down carefully. Even the best fitting covers can move slightly in strong winds and rub the outside of the windows..
IIf I was to buy anything similar it would be a cover for the roof only to gaurd against bird droppings, leaves etc. but this still leaves the problem of long bungee cords potentially rubbing against the sides of the van. I would treat the roof with a good wax polish so that it hosed off easily or one of the winterising sprays e.g. Fenwicks. I would use cardboard to obscure the windows on the inside, avoiding leaving the blinds down for an extended period - won't look wonderful but much easier and cheaper.