Went with collette to France/Italy on summer 2003, i would grade the service as 6.50 from 10 scale (compared with tauck, 8.5 on ten and globus 7.5 on 10). .
The tour guide was a young lady who was bringin the tour for the second year. In Rome we took two options for dining on two nights in a row, the second night we went to the restaurant owned by the restaurateur we went on the first night thus the food was very similar and so was the serenade.
The hotel choice was good though at one place it was not clean for three star hotel.
The bus went on flat tire on two different days (you could call it "memorable" looking from different point of view!) and the driver got lost on the mountain, probably for an hour!, before the tour guide stopped and asked a car going on different direction (direction we should take). .
If you are looking for "memory" go for collette, otherwise, I personally prefer Globus.