Welcome to KZR! Looks like a nice bike. I hadn't realized that the 79's came with the Mark II engine. Only thing you should be concerned about is the normal issues on 34 year old bike. No different than any other bike. Since you own two older bikes, you already know the drill (check brakes first, then tires condition and age and so forth). As for any inherent issues with the bike, I don't know of any for that model/year. Bullet proof engine, and I think a lot of the frame issues were improved by 79. Lots of power. Should be a very enjoyable bike.
