When we were in CC in March we toured exclusively with Anwar and were very impressed. We didn't zipline but went on the cave tubing / Belize zoo excursion. We heard good things about he other tour companies as well, like Carlos, Ragamuffin, Mario. During the slow season you will probably find that the tour companies will band together and if each of them has 2, you'll all go in one group. Have a blast!!