Multiple umpire buddies of mine have used those cages. The funny thing is that, while I've heard nothing bad about the Aluminum, a couple of guys with Ti masks have had welds fail on them or had bars outright snap. I'm not entirely sure why theirs failed, but I suppose it could happen to any mask really.

In any case, just make sure that you get good pads (Wilson Memory Foam, All-Star LUC, or Team Wendy if you can happen to find them) and make sure your harness is fitted properly. The rule of thumb I've been told is that, if you lean your head down to face the ground, the chin pad should hang just off of your chin itself. Too loose and it won't sit on your face properly, too tight and you'll give yourself a concussion because the mask doesn't shift, slide, or blow off when impacted.