These are the toe links from Tarett that I used on my Cayman. I imagine these are the teflon style you described.
Very happy with them and they didn't affect the ride quality. I do 2-4 DEs / yr and have the camber set at -2.0 in the rear. These arms are miles ahead of the factory egg-shaped bolt as far as keeping your alignment set. But the majority of my Cayman's life is on the street, so ride quality is important.
Anytime you start replacing factory bushings with harder materials, you're going to feel it on the street, however it's negligible to me with these arms. I have quite a bit of Tarett's engineering in my suspension. The only item that affected the ride was replacing the hockey pucs, but it wasn't bone jarring, just harsher.
I would recommend buying those toe arms. And another item to purchase are the monoball bearings for your LCAs. If you're still on the factory bearings, they're probably shot. If they're not shot yet, they will be when you start to do DEs.
Be careful - Tarett products are crack for the track or street addict. They have a crapload of great products and you can ring up a big bill if you're not careful. To keep things under control, I tend to add 1 or 2 of their items ea yr. My next purchase will be droplinks.
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