i wonder, is the OP replacing the sprockets along with the chain??? if not, that'll cause premature chain wear.
you're right its a did erv 520 chain.
i think you're right hondajim. i most likely read his post wrong.
OP, the biggest issue you need to worry about is chain slack. if there's too much slack then no, it's not safe to ride. you look to be at the end of adjustments so pay close attention to that. the other issue is to make sure your chain isn't kinked or binding where the o-rings are missing. if there are none, you should be ok in the short term (i wouldn't go far though) and make sure to lube the hell out of it. if there is any sign of binding or resistance, it's not worth the risk.