i'm a huge fan of French history and was super excited for this tour. It met all of my expectations! We covered most of Versailles (although I feel you could definitely spend 2 days there). Our guide was very informative. I also felt the tour was worth it because the crowds are huge and it was nice to hear what the guide had to say rather than peering over heads to read signs. Overall, awesome tour!
Monet's Garden itself is amazing. And I really don't feel you need a guide for it, it's something best done by yourself. However, this tour does say a professional guide will be with you and for those who are banking on that there was no guide with us at the gardens. Someone picks you up in Paris and drops you off at the gardens and you meet them a few hours later. It is a small group. It was completely fine, but thought I'd mention it for those who are expecting a guide through the entire tour. On the way there he did give us a bit of history of the areas we were driving through and was very accomodating to our needs/ things we wanted to see on the way. Giverny is quite far out of Paris so unless you wanted to rent a car, a tour would be the only way to get there. I feel like it was worth doing and I loved it, but a bit expensive for what you get.