Asking this question in a chondro forum will probably get you some biased responses. I think both make good display animals but both can be stressed in high traffic areas of the home which can lead to problems over time. Either one should be well established before placing in a display like setup, in my opinion. You need to ask yourself what you are able, or willing, to provide. They require similiar conditions - heat, humidity, and proper ventilation. Chondros need no special lighting and normally feed on f/t rodents which can be purchased in bulk. Chams require special lighting and vitamin supplements, along with a good supply of crickets, wax worms, etc. Could be a tough choice but my guess, since you are contemplating the two, is that you will ultimately end up with both.
Bart