I guess that all depends upon your local climate -- something we all have to take into account growing things half a world away. Family in Florida can easily grow low-lander Nepenthes in hanging baskets next to a patio; I require heating.
In Northern California, highlanders can be grown to a large degree on a windowsill but those that require a Tb drop at night really need that extra punch. The gel ice works out here as needed. Use larger sizes then if melting is a problem, I suppose . . .