I would really encourage you to go for it! Good Pilates instructors are really needed!
I have a "fake" Pilates certification (2 day workshop) and I would love to be able to study for real certification locally. Unfortunately there are no local resources, so besides the cost of the instruction, I would have to invest a substantial amount of time and travel away from home for an intensive course. I'm already away from home much, much, much too often, so right now it's out of the question.
What do you want to get out of it? Just to spread the love? To bring your own practice to another depth? Would you expect your investment to pay off financially (probably only realistic in major urban areas)?