Interstate had large tank and taller gearing, Roadster was almost cute! Both lost 5mph by the end of their lives and fuel could drop to a shockingly bad 40mpg by the time emission laws began to bite. Post ’75 Mk.3s offer the best reliability. Last models had electric start and gearchange on the left side. Some well sorted bikes and lots of finicky if expensive stuff on offer. Make sure you buy the former if paying serious money.