Of the plants listed here, I would say that alata (the green/red variety) is by far the easiest to grow for me. I have yet been able to produce conditions where it wouldn't pitcher (indoors, outdoors, highland, lowland, intermediate) and it in general seems to be a nice plant. The pitchers aren't very ornamental/decorative, but they are pretty in their own special way, and can be fairly large. I'm not sure how large they get, but I know at least seven inches. I can also wholeheartedly recommend Nepenthes x ventrata ( a hybrid of alata & ventricosa) these two plants.
Patrick