I have used the table saw model, the PSA adhesive discs. I think that the H&L discs would be a great improvement,that way you can change disc grit as you go. The one I used is good and was like a jointer in sanding the saw kirf marks off the edges of boards for glue up. The metal disc has a 1 degree camber built in to it so that once it goes past center the back half of the blade is not sanding and being lifted off the table, when sanding between the disc and the fence. I am not sure what kind of sanding you will be doing, but it works good with the miter guage and fence, I never used it free hand so can't vouch for that. The down side has been mentioned by Doug in that your table saw is tied up with a sanding operation and has to be changed back to use as a table saw.
Dougs suggestion of looking for a combo belt/disc sander used is a good one. I picked up a 6" disc and 36"X4" belt sander for $85. years ago and it is still running,a little noisy but still works.
I just read the link you put into your post , and the disc does have a angled face on one side,the side for the sanding disc. The other side is flat for saw setup. One reviewer did say he bought a 2nd H&L pad for the back so he could mount 2 different discs and not have to stop for setup. This will work for freehand sanding , but be dangerous for sanding between the disc and fence. If the flat side is towards the fence and when you sand it will tend to raise up when it goes beyond center with a tendency to be thrown back at the operator. Also if it does get held down and makes it through,it will show a burned edge.
Last edited by Herb Stoops; 11-18-2018 at 05:46 PM.