Ok ... I'll weigh in here and you know I had a recent experience with spray basting.
First ... the reasons I love and hate spray basting.
Love it for the result. It's smooth, the basting is complete (ie no "un-basted" areas), I don't have to pull pins out or get basting stitches caught in my hopping foot ... I just put the quilt down and GO, it stays basted for a good long time, and you can pull it apart to adjust then stick it back down.
Hate it for one reason only ... the mess. The overspay - which cannot be avoided. I'm not talking about overspray of the area you are aiming at ... I'm talking about the particles of mist that WILL drift through whatever room you are basting in. It's inevitable with an aerosol product ... it drifts.
Soooo .... as you know I recently waited patiently for a decent warmish day with little wind to bring my quilt outside to spray baste. For this quilt spray basting was the best option because I was using minky as the backing and minky is slinky - or as my LQS lady said as she was (attemping to) fold the minky "it's like wrestling a wet seal".
So what I did was spray baste outside, then bring my quilt top indoors and spread it out on the minky which was laying on the floor. Yes ... I needed a friend to help me. Depending on the size of the quilt (wider than the span of my arms?) and the weight of the backing (minky is heavy) and batting, I may not be able to use a wall. The width of this quilt was wider than the span of my arms so I could not place it in place with any confidence. The minky is heavy and and its a knit so I was concerned that it would be stretched at the bottom. So on the floor it went, and yes we did have to adjust it (the adjusting I did on my table). If I had a table large enough I would have used that, but I didn't want to do it on a table where the sides had to drag off the edge.
So IF you decide on spray basting 1) find a friend and 2) do it either outside or in a room/place where you don't care if everything around it gets sticky.
I really really LOVE spray basting ... so many pro's ... I just need to work around the one big con.