The consensus is that Banff is highly recommended. Don't go here expecting a bucolic Alpine village. Banff in summer is a very busy place. Lots of information and links. From the Alberta Motor Association.
Parking is often difficult and traffic is often congested.
Banff National Park is a must see but accommodation in the nearby town of Canmore is more reasonably priced and staying there permits you to travel throughout the National Park while avoiding the tourist crush in Banff townsite. Rates, reservations, schedules. A bit of the history and attractions of Banff and the surrounding Canadian Rockies. Webventures Banff Compile personalizied postcards from Banff.