Personally, I think a 40g TANK is not suited for a ball python simply because TANKS (especially the large ones) are meant for FISH.
Back to THIS, I see. Well, in THAT case...TUBS are meant for SHOES. See, I can do it, too!
As for tanks "sucking at keeping proper bp husbandry", when was the last time you saw a glass tank performing anything? I'll re-phrase it for ya, k? People suck at doing stuff.