I have the switchblade from ebay but haven't gotten around to getting it to work. I got the key cut at a local locksmith AFTER I took it out of the housing because they couldn't cut it while it was in there.
The dealer wanted $50, I believe, to attempt to program the transponder. That's the part I haven't gotten around to it yet. The key itself (not the remote) works in opening up the back window. I also programmed the lock and unlock buttons with some help from the internet and those work. With the switchblade, you lose the panic function and the rear window down function, just something to think about it.
Overall, it is a pretty neat idea and takes up less room in your pocket. If you're into that kinda thing, which I am, then go for it. Plastic feels a little cheap but I think it should be sturdy enough for everyday use.