Hi, I use a LPL folding one a fair bit of the time.
They are very stable, have an adjustable locking cold shoe, and will also take a cable release should you wish to use one. I have used mine with Medium Format as well as a D800 with power pack (just to give you some idea of how strong they are).
I'm not sure if they are still available new but they can still be had from Ebay.
Hope this helps.