I much prefer fluorescents. I havea 400w MH light, and while the plants grow well, they clearly suffer from reduced humidity. My nepenthes pitchers don't last as long, and my pings don't color up a well. Also, it costs a lot more to run.
I like the four foot fluorescent tubes for most applications, because you can put a bunch of drosera, ping, and utric pots under them and get them close to the bulbs, and then something like a couple fluorex fixtures for the taller and variably sized nepenthes.
Capslock