Darlingtonia are not very delicate when it comes to cold. Their issue is heat. It's not at all unusual for native colonies to see temperatures in the 20's and teens sporadically. Snow is common for many colonies.
The distance a plant has to travel by USPS Mail is largely irrelevant, since Priority Mail often takes no more than two days to travel the breadth if the continent. Emphasis should be placed on who sells the best plants, not how far from you they are.
Well, not an issue any more as it finally warmed up a bit. However, I have decided to delay the cobra lily purchase until I see how I do with my nepenthes. If I can't keep a nepenthes alive, I am not going to risk a cobra lily. Carnivorous plants have been an interesting challenge to me, catering to the different needs of all the plants within a limited space has been interesting but I have managed ok so far. I think giving myself time to build up experience with easier CPs will be good, and I did promise my mom no more new ones this year.
Nothing compares to the joy of growing a plant from seed and watch it prosper.