I got mine from ebay- people buy bikes with them on and sell them unused. I use the DH version sometimes for the slightly stickier rubber but by and large I use the SX.
Never had any problems with the sidewalls, maybe because I weigh nowt, I’m not hard on tyres generally… having said that I’ve hit them hard enough to pretty much destroy a rim without flatting, another time I did flat the rear at fort william but also flatted the Flow Ex it was on 🙄 They’re not officially tubeless ready but do act like it. Hmm, can’t think offhand of any other time i’ve managed to flat ’em, or the Clutches I had before (*), there’s a fair number of cuts on one of them but nothing troublesome.
Basically they’re just what you think- a halfway between single and dualply. I suppose only you know if that’ll work for you.
(* Clutch not so good)