As a whole GTPs are easier to keep as ETBs. As far as wild caught, Stay away. There are quite a few very reputable breeders for both ETBs and GTPs that have captive bred and born. With that said, most likely you will have to get on a waiting list, but it is worth it. CBBs of either species are better eaters and have far less problems than WC. WC, especially in ETBs are prone to regurgitation syndrome. With both, your husbandry with need to be finely tuned before any snake arrives, especially the humidity. GTPs will do fine as adults in a 24x24x24. Adult ETB will do fine in 36x24x24. At least that’s what mine are in. As far as temperament, as a whole neither are a “holding” snake. They are more of a display animal. With that said, some people handle them just fine. I choose not too. CBB of either GTPs or ETBs will be expensive and if you are looking at something real special, Amazon ETBs will cost you thousands. A clean northern CBB emerald will start at several hundreds of dollar and a clean GTPs will be the same