I'll assume you're meaning the safety frames over top of the baskets. Their only real purpose is to keep someone from walking into the spinning baskets. And yes, it has happened...
I'd be more concerned with parts. If the gearboxes seem to be tight, I wouldn't be too afraid of it. Might be an idea to look on the net, and see if you can find parts like the arms, and tedder teeth. Teeth may be generic, and used on several other brands, the arms may be a different story. If you get it, order some spare teeth, you'll need them. I've broken 5-6 in the 15 or so years I've had mine, by simply dropping in a groundhog hole I didn't see. Goughing in the ground will snap them in a heartbeat.
Just go over it before every use, and check the bolts in the arms, and make sure they are tight. I've had them loosen up, even with the nylon type lock nuts on them. I've seen more than several tedders at auctions with arms missing, and more than likely, because the user didn't go over the machine, checking to make sure bolts are tight.
Otherwise, they are a great tool to have. Especially if you are in an area like where I live, and you may only have a 3-4 day window of no rain, and you need to get heavy hay dried to bale. I wouldn't be without one now.