Sandpaper recommendations for DIY power sanding disks for bowls

I am making several power sanding disks for my right angled drill to power sand turned bowls. Basically I anchor a 1/4” shaft into 2”, 3”, 4” & 5” diameter X 3/4” thick wood disks. I then glue 5/8” +/- foam to the disk. Now comes the sandpaper issue hopefully starting @ 180 grit upto 400 or 600.

Option 1 – Glue backed sandper either in sheets, disks (no holes) or 6” wide rolls.

Option 2 – Hook & loop backed sandpaper in the same forms as option 1.

Klingspor seems to have the most economical solution that I have found which is a) 4 1/2” wide x 10 meter rolls in Aluminum Qxide Serate @ $ 21/roll. OR b) 6” wide x 5 meter rolls glue backed for $ 10/roll in Silicon Carbide.

I have 2 questions: #1 – What is the difference between Aluminum Oxide Serate and Silicon Carbide and which is best for finish sanding bowls, etc.? #2 – Anyone have a better resource for sandpaper than Klingspor?

All suggestions are much appreciated.

-- Ken, Michigan