I'm so happy that you are finding this info helpful. :thumbup:
I was almost impossible for me to baste a quilt on the floor too, but this process makes basting actually enjoyable for me!
I'm sure you could pin-baste this way as well. I have spray basted (with 505 spray) smaller quilts the same way with great results. It makes it easy to achieve a pucker free basting job without a second person to help.
My MDF boards came from Home Depot pre-cut at 8 feet long and primed, so all I did with this set was staple on the flannel. I have another set for baby quilts that I cut down to 5' lengths, but I know any lumber yard will cut them for you, usually for about 50 cents a cut. These boards were the most inexpensive option I found, but I'm sorry I don't remember the exact cost; I'll check for what they are called and for the price the next time I'm in Home Depot and let you know. If you already have 5/8" plywood or mdf on hand and want to cut your own, you certainly can. Whatever kind of board you use, it is very important that they are extremely straight and even. Otherwise your quilt will get wonky as you roll it up, and then you'd a have a bit of a mess.
By the way, I finished the FMQ on this one and will post pictures as soon as I can.