Have you looked a Peregrine (silicon on sapphire)?
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They can do 20 ns, and it isn't the fake digital 10-90% rise/fall time. It is more like a 50 mdB settling time. (Something meaningful/useful for analog/RF.)
Of course, GaAs switches are horrible with the gate lag when looking at something like a 50 mdB settling time. (Because of the gate lag.)
The low frequency power handling of various switches can be poor for various technologies. Peregrine has been working on that---not sure exactly where they are with it.