The KEY to them being durable is having them screwed on tight!!!
I've bent a few over the years, mostly on judos cause I get lazy and don't check to see if they are tight after every shot. What causes any adapter post to bend, and yep I've bent steel ones, is not having them on tight and the gap between the base of the adapter and the end of the shaft becomes the weakest link.
I try and use plumbers tape on all my judos and that seems to work pretty good at keeping the from working loose on repetitive shots. I do have some hog heads that are locked down tight with epoxy just for good measure. But, my Bheads don't usually work loose as I'm not shooting my sharpened ones a lot at targets and I check them before every hunt. (I still would and do IF I use steel adapters)
Aluminum adapters have also served me well for 2 and a half decades.....and I have them on most all my arrows. Only a half dozen have steel adapters, and I save them for special occasions and don't use them often. I've killed most of my hogs with aluminum, and only two with the steel.
So, I don't worry about aluminum adapters at all. I think after all I've killed with them(angled shots-busted ribs and all), and all the target and judo shots I've taken, I'd know if they were a real problem.
Just make sure you get them screwed down tight and you shouldn't have a problem. I never have in that case.