I spray baste and the spray I use holds great.. no need for pins.. no slippage.. and it lasts until the quilt is washed! I have sprayed a quilt, rolled it up and let it sit for a week before I was able to start quilting it and it did great!
I actually baste mine outside. I have done it on my patio. Cleaned it off and covered with a kingsize sheet. Now I use 3 folding tables. Much easier on the back!
Barb C.