Actually an UTH simulates the 'wild' better than a heat lamp. Ball pythons keep warm by residual ground heat. They're nocturnal animals. They don't go out in the sun and bask. A UTH simulates residual ground heat the best.
A heat lamp is more suited for an animal that needs sunlight and arid conditions in my opinion....
If you use a heat lamp or UTH, it doesn't matter. Just do what works for you and your animals. I personally think an UTH is better than a heat lamp. But that's just my opinion, which I am basing on certain known facts.
And snake's aren't living in a glass box in the wild either. :\