Wife and self (70ish and usually independent travelers) took the elderhostel Copper Canyon (mexico) trip two years ago.
Plus side: luggage handling was painless, trip transfers well organized, not a push-push schedule, no hurry up and wait on activities
Minus side: stuck with large group- no relief if no compatible travelers as companions, group dinners were preset with little choice from menu
Would recommend it for third world travel areas where local transportation could be haphazard and excessively time consuming.