Conventions in the Classical world are a killer! I know several players that use that support. Those that do seem to like the stability it provides. It is very adaptable. That said, I have had bad luck with suction cups on my guitars. They don't seem to stick very well. They are fine for a while, but who knows when it will fail. Not a good picture for a performance!

I have gone in the opposite direction! I French polish with Royal-Lac then rub down with fine steel wool and put on a coat of wax on the body and top and buff that out by hand. Gives a very nice sheen without being highly glossy. Kinda like the look. That said, not a good environment for suction cups. My favorite attachment is the one that attaches with Magnets that are placed inside with removable tape, like those wall hangers use. That support is very adjustable, and just pulls right off. While on, it's solid. Can't remember who developed it.