solid state, cheap switching of multiple AC forms?

Looking for thoughts on switching of AC. I will list some basic parameters. Goals are to achieve a faster switch time and have more cycle rating while also reducing cost. Really, a mechanical relay works perfect other than they have some delays and will eventually wear out. It might be that the mechanical really is what we should stay with but still worth a search.

AC - 5-200hz, .1-1VAC, 500mA, N.C. function (latched when not powered).

Stick with the relays - latched when not powered is a bit of a killer requirement otherwise.

Relay reliability curves are well documented by OMRON with load types and rated current.
Ignoring this or using cheap relays will get worse results.

OMRON is best in this category.