I've got a large (well, pretty big!) heavy duty keyboard case that I've had for over a decade ... I forget the name brand (which, oddly, isn't on the case), but it's built like a tank.
It's also heavy like a tank! (Well, it's not THAT bad, but I'm getting up there, and I really don't see myself hauling it around any more.)
I am pretty sure it's TSA approved. Sure feels like it.
It's no big deal if you're in your 20s and touring, you could easily toss it up and down and around and down the stairs, and still protect your keyboard.
It's been on the bottom of lots of vans, with lots of guitars and other cases on top, and it's got nary a scratch on it (though I couldn't completely remove the stickers I put on it! I'm sure they'd come off with some rubbing alcohol if they bug you ... or you could just cover them with more stickers)
The latches are fantastic.
What else? Oh, the foam on the inside is the only thing not as good as it was originally ... No big deal, IMO, just shove another piece of foam in, and you'd be good to go.
The closest case I can see to in on line is this road runner case (which is $349). Actually, I wonder if mine is a Road Runner -- it looks almost the same (though mine is a little bigger).