I have been on 3 RS Tours, with a 4th one planned for next year. (10 Day Venice, Florence, Rome, 7 Day London, 7 Day Paris). My 65 year old mother and I (29) went on the 10 day Venice Florence, Rome tour in May 2013. We are both in average shape and have no knee or hip issues. We each brought a RS bag (Mine is the backpack, her is the one with wheels) and a day bag. Overall I thought this tour was fine for carrying our own luggage and we did not expereince any major issues. The other people in our group (mostly my mom's age) did not seem to have any problems either. I have broken down specifics though for each city.
- Venice: We arrived via train from Rome the day of the tour, then took the vaporetto to the hotel. The vaporetto stop is literally right in front of the train station, like maybe 1 minute from the entrance. The vaporetto took us to a stop that was about a 3-5 minute walk to the hotel (Pensione Guerrato). At this hotel there are no elevators. Our room was on the top floor and there were 67 steps to that floor. Climbing those stairs with luggage wasnt fun, but we managed and it was only 1 time up, and then 1 time down when we left. However there are a few rooms on the bottom floor of the hotel so no steps are involved. The closer it gets to the tour you might could speak with the hotel and ask them to place you in a lower level floor. Transfer from the hotel to the bus when leaving Venice with the luggage was a little bit longer walk. We walked about 10 minutes to the vaporetto stop (crossed over the bridge, with about 8 steps on either side). Rode the vaporetto for maybe 15 minnutes, then got off and walked 2-3 minutes to the bus that was waiting for us. Driver helped us load our bags under the bus. I managed a little better with my backpack than my mom did with her wheeled bag, but overall we didnt have any major issues. All of the group seemed to keep up and nobody seemed to have any issues. The only problem was that is was POURING down rain during this entire process, but we had umbrellas. Venice was the most challenging city on this tour in terms of walking length, flights of stairs, etc with luggage.
*Florence: The Bus pulled up across the street from the hotel. The driver helped us unload the bags and then we crossed the street with the bags and walked up maybe 15 steps to the lobby. Our room was on the bottom floor so we didnt have any issues, most of the group stayed on the same floor, as it was a larger hotel. When we left the bus pulled up in the same spot (across the street) and the driver helped us load our bags underneath the bus. I don't believe this hotel had an elevator.
*Rome: The hotel was half way down a small alley, so the bus pulled up at the base of the alley and the driver helped us unload the bags, and then we walked up a slight incline to the hotel, maybe a 2 minute walk, but (slightly) uphill. This hotel had an elevator!
As I said, carrying our own luggage physically was not a major issue to us, and nobody in the group seemed to have a physical issue with it either. If you have never been on a RS tour though, be warned they are very active. My mom wore a pedometer and most days we walked 5-10 miles, but we did a lot of siteseeing on our own without the group during our free time.
The city tours may be a good option for you if you are worried about carrying your luggage. You stay at 1 hotel the whole week, and at both the London and Paris hotel we stayed at there was an elevator, so no issues.
I have not been on a Tauck's tour, but it sound like it is a very different experience than a RS tour, (luggage service, trains, 5 star hotels, etc) Not that there is anything wrong with that, but just be prepared the RS tour will probably be vastly different, and you should be sure you are ok with that. Sounds like you have done a lot of research though. The RS Tour Department is VERY helpful, and if you call them they can answer most everything, even if you havent booked a tour.