I wouldn't look at any of those for sandpaper. I do buy mine online these days but I'm mostly buying for specific Festool models. I have a few rolls on the go for hand work.
This cloth backed stuff is really good and durable. I don't use it on machines though.
Prefer sheets at they fit into the existing storage but rolls seem more common these days
Amazon, B&Q and Screwfix are all have pretty poor offerings