I did a tour with Collette in December 2012. (Rome, Florence, Sienna, Murano, and Venice)
I am not a fan of guided tours however I felt Collette did a good job in most aspects. Tour guide was great to work with, I got sick on the trip and they helped with getting the medication I needed. Our flight got delayed by 10 hours in Germany and Collette was on the ball and had the bus and a representative waiting for us even that late at night. They even helped us get our luggage and find our way around the airport in Rome. Bus driver was good as well and for how scary it is to drive in Italy I felt safe with him behind the wheel. Side tours such as wine tasting, tour of monastery, and castles was very in depth and not something I would have thought about had I gone on my own or even know how to go about setting up. Several "gift shops" or places we stopped had deals to give us discounts on our purchases since we were with Collette, which was an added bonus.
The trip over all was pretty good as they still left us ample time to explore on our own for the most part, again I'm normally not a fan of being told when and where I have to be while on vacation. These were some of the positives.
The things I didn’t enjoy were some of the choices of restaurants for included meals, they left a lot to be desired. Being in a place known for their amazing food I was a little disappointed. Since we were such a large group it seemed to take quite a while to get food out and I feel the quality suffered due to this. I did feel rushed in the mornings to be down in the lobby for the tours in each city that were given by a local tour guides, these were not that great and would have preferred to skip these.
I would still travel with Collette again for locations I have never been or don't want to deal with the planning. I have been looking at tours for Costa Rica or Ireland for some time this year and will keep Collette in mind when looking to do them.