I think the 650's system is considered to be better than the manual adjuster ones. At least the chain is always adjusted properly, until the chain stretches and wears. So, the chain does need checking and replacing when worn. My chain had 54k on it and probably could have gone another 5k before it would absolutely need changing. I did it anyhow since I was there already. I believe Bandit's was about the same mileage. But I have heard of others with 30k needing chain replacement. May have to do with oil changes, and if the bike was flogged continually.
Unfortunately, parts other than the chain are no longer available new. The left guide was available until recently, but I heard someone say they couldn't get it from Honda now.