I agree with what both William and Jon have already said, but I would add this too. The advantages for me are that it doesn't clog; it seems to last longer than traditional paper backed abrasives (but I suspect if you pay enough for traditional abrasives they will last a long tome too); it's based on a synthetic backing which is very user friendly in terms of bending to shape without that inevitable loss of grit along the crease, or on coarser grits, that "breaking the spine of a book" effect you often get with cheaper abrasives; it can be used for wet sanding; there is no physical grit welded to the backing, to come off in use; it comes in very handy sizes without the need to cut up larger sheets or rolls, and most importantly, I seem to get better results with it with far more ease and far less effort than with other abrasives.
However, a box of 50 sheets is about £18 or £19 these days, so that's a heck of an outlay if you want to adopt it across all the available grades, but it's possible to buy a sort of trial pack which comprise 10 each of 5 grades. Thereafter, if you decide to stick with it, you could begin to change over starting with the finest grade, then invest towards the coarser grades as budget allows.
Can you tell that I'm a big fan of Abranet
