I have used footstools and a large Dynette cushion. They work but both have their drawbacks. I like to keep my feet flat on the floor for my back and I find that the cushion tends to squirm out of position during a longer piece. So, I was on the look out for a new guitar support.
I purchased the Tenor [mfgr name, not vocal range] Professional Guitar Support [TPGS+] from Amazon for under $30 a few weeks back. I am quite pleased with the way it works and adjusts. There are suction cups involved, but so far no apparent problems on my nitrocellulose lacquered finish. I remove it each time I play. The suction cups go on easily, hold well and remove quickly. It can be adjusted so the guitar top can be angled somewhat up, by positioning the suction cups at an angle on the guitar side [one lower than the other]. The support really folds down flat and is small enough to fit into the case pocket easily.
Thought I would post a newish product here for those still looking for the right positioning tool since I am very pleased with it.
Added the pictures below. The leg material is two velcro strips that can be adjusted tighter or looser to help angle the next up more or less. I have enjoyed using this simple device.
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