I am a tour fan and have done 8 Rick Steves bus tours and 8 Road Scholar tours but this tour would not appeal to me at all. As others have said there is no time to actually see anything. This is NOT a typical bus tour in my view.
While I am not familiar with this company, I am familiar with the Asian tour model by 2 other companies in the US from time on Trip Advisor. These tours advertise they are bilingual but the continuing complaints I see on TA from English-speakers is that there is minimal information given in English. The model involves leaving very early in the AMs and getting to hotels late in the evening. In the US many of the food stops are Chinese buffets or if that's unavailable, fast food. Most breakfasts are the ones provided by the hotels, so I question the statement on this tour info saying American breakfasts. The US tour model involves a lot of stops for very short time - usually enough to get off the bus, take a picture of said monument, scenic site or whatever, then back on the bus. They are usually priced inexpensively but you are expected (Many reviews say the guides demand ) cash tips daily for the driver and guide. Another complaint I see is that the guide collects money for admission fees that are way above what the actual fee for the site is. Other complaints are regarding the location of the hotels which are usually out of the city center, however with early departures and late arrivals there is really no time to visit anywhere on your own anyway. Some of the reviews I have read on Trip Advisor indicate people were left when there was not a clear time they were supposed to be back at the bus or were late by 5 minutes.
IF you decide on this tour please scour the internet for reviews of this company. Check to see that information is provided in the language you expect (not a problem if you speak which ever Chinese language they present in). Check to see what the daily tip amount is. Check to see where the hotels are. Check to see where the lunch and dinner stops are. Check to see how often there is a comfort stop. Check the itinerary carefully and note whether they say you SEE a sight (can be a drive by on a bus) or VISIT a sight (which means get off the bus and go in). Check to see if good things are covered only by optional paid tours. As Brad says, check to see if they take you to gift shops or demos where you are supposed to buy something.
If you want an enjoyable tour of Europe, I'd recommend spending more money for a better tour company. Do some comparison with the RS tours covering a similar area. Look at the the 14 or 21 day best of Europe itineraries which cover similar territory. I didn't price compare but I'm sure the daily rate is at least double but .... you get what you pay for. I'm not saying Rick's is the only tour company but it is a good basis for comparison. See what entry costs are covered, what meals, what sights you visit. Neither Rick Steves or Road Scholar stop at gift shops or build shopping opportunities in to your itinerary in lieu of seeing cool things. Of course shoppers infiltrate both tours, lol, but they are on their own for finding shopping.
BTW, you can order the RS tour book which of course is free. Sometimes it's good to have a copy to flip thru.