Some would say that. If they made them bigger I would have gotten a larger one. As far as size, I believe it is suffice. I would say the 24x24x48 is too narrow.
As long as the animal is happy, and you do your best, as a keeper, to replicate itsi natural environment, I really don't think it matters where the extra 12" comes into play.
Can anymore give me some advice regarding my lighting? I am getting a 4 feet high hybrid enclosure with live plants and my friend suggests that I get a Exo Terra reptile uvb 100 and Exo Terra daylight basking spot 50W. My ambience temperature is 28℃-31℃, 60%-85% humidity. Are the lights okay?