I use one too, and love it, but find it's even more secure with the neoprene mats.I've never felt the need. The guitar rest I use (a De Oro - thank again Peter!!) has a strip of leather that sits on the leg, rough side down. It feels very secure to me.
I do use several types of antislip mats, but only those showed in George Crocket's pic for the most fragile guitars.
It also helps if the fabric of your trousers is slippier than normal. Some fabrics can be quite slippy and the mat helps then. I rarely use a footstoll as in the past I've had problems with my hip ( not guitar related) , I find having hips level helps.JohnB wrote: ↑Mon Apr 16, 2018 8:45 pmI'm curious about this, after the thread show so many people using mats.
Personally, I use a footstool and my guitar feels very secure and stable, and I can't see how the stability would be improved with a mat. (I suppose the stability depends of the geometry of footstool height, chair height, left upper leg angle, angle of the guitar, etc.)
Thank you: I got mine from a Trekel booth at a festival in Germany, I'd forgotten the company name. But they are, basically, just pieces of 1mm neoprene and agree, better than the kind described by the OP.