Only had a couple chances to ride in them, but I love them.
Tough to say if they're safer, I'm no expert, but I'd say they should be much safer than normal suspension seats simply because they'll hold you in better and the head-rest extends higher up, past the center of your head, so they should be more supportive in a crash. Not sure how they'd stack up against and FIA homologated seat like a Sparco evo, I assume they'd be comparable, but as far as I know they have not been tested head to head, so I doubt anybody can tell you for sure.
Not sure who would have some in stock, as I've never seen a "standard" one, everybody gets custom colors and materials, but call around, somebody will have one sitting in their showroom for you to take a test-sit in, closest place I can think of to call in NorCal is Poly Performance, though Shaffers may have one as well.