I went to Europe through Charming few years ago but the guide was so so so .... bad (it depends how lucky you are, if your tour being allocated a bad guide, then ???).
e.g. one of the tour member's son was sick during the tour, he didn't show caring or helped her anyway (she went there with her 2 sons, only the tour members helped her to take care of her sons). He always said that something wrong with the meal arrangement and just refund a little bit money to the members and asked the members to arrange the meal ourselves. He even never reported or reminded us the weather of the country that we're going, even we asked, he just said normal or not bad, but the actual situation is totally difference. All the tour members complaint about him all the way, but we scared that if we didn't give him the tips, he would hold our returning ticket.
Upon my return, i also made the complaint to Charming but they didn't give any feedback and apologise.