Boy yea that roof and seams look nice.She's gonna be buttoned up good.Part of the decay of anything out in the weather is a combo of that darn sun breaking things down too.People with equipment like you know this first hand.Tires,paint,belts,and you name it camper roofs too.That's one reason why I love my out buildings so much to preserve things,and I'm sure you do too.
One reason I bet why this campers' roof went south in the first place besides maybe some mishap done to it but mainly neglect.Your putting right back to like new it looks like.