I think the Natural ones might just be testing the market right now. I got them about a month ago, but haven't seen them since. I have not seen the lime either, but I love love love the Tostitos Lime chips. I think we have the taco here too. I've tried the guacamole and they're OK. I've had a different brand that I liked much better.
Dang it! Now I'm going to have to get some Doritos next time I'm at the store.