I think I'd rather give my snakes a temperature range and let them figure out where they want to be, with the caveat that I keep a variety of species with a wide range of temperature and humidity requirements, so keeping them all at a constant 80*F or 82*F or 85*F would mean that somebody isn't going to be very happy.
Plus, doing so would mean putting in separate HVAC for my snake room since right now it's controlled by the house temperature. If I had a separate building on my property that would make a big difference.