The Matrix ISO rims are a royal PITA when it comes to tire changing. Avoid those!

The Arayas sometimes lose a tire bead and blow out, i.e. the bead "hook" isn't a hook but a mere semi-circular nub.
I've lost one each one was wired and one was folding. In both cases the tire blew off after extended downhill braking, and both times the tire started thumping against the fork leg for a few turns before going "BOOM". I always run 90psi up front, but also should mention both tires were a bit dry from age so the bead area wasn't exactly grippy like a newer tire.
I even had a 3rd tire blow off of an Araya rim, in my livingroom and not while being inflated. Again, the tire was well-aged, and again, the tire didn't come apart, it just crept off of the rim.

I've not had this problem with any other rims except perhaps an older rim with no bead hooks at all. I do know how to properly mount tires, not trapping the tube, etc.

So, moral of the story might be that older Arayas are fine for modest pressures using reasonably fresh tires. If these Arayas are singlewall, then tire changes will be particularly easy but the rims might be on the heavy side and not particularly strong.