Lynn, I think it's the combination of sun and humidity that does in a lot of the succulents in this area -- many can handle dry heat, but when the average daily humidity is 75%, the mix is just too much. Or a 6" rain in 12 hours really rots 'em out fast.
Aloes do very well even in-ground in full sun, and there's supposedly an Echeveria runyonii 'Topsy Turvy' that someone in my area is growing (don't know in how much sun). Sedum mexicanum and Sedum makinoi 'Ogon' also grow well, but also not in full sun.
