I've got a set of the East Bear t/c rods on my s14. I got them from Wayne at Phase2motortrend for the same price as the Tiens. I picked the East Bear units for two reasons: 1) Teins were backordered from Japan for 6 mos.; 2) I don't really like Tien's reputation for some things (rust); and 3) Wayne hooked me up by lowering his East Bear price to match the Teins. (cool guy, in my experience).
Generally speaking, I think all of the brands should be equally good - given that it isn't anymore than a threaded aluminum rod w/ a spherical bushing (pillow mount) at the end. Barring differences in the bushing, there's not much room for difference.
As for performance - they definately made a difference. I am running stiff sidewalled street tires w/ a tired stock suspension. The effect of the t/c rods felt like I boosted my tire pressure by about 15 lbs. Much lighter steering, way more road feel (you will feel EVERYTHING), and much more feedback when the tires are at their limit (on track). The drawbacks are that you feel EVERYTHING - every expansion joint, crack, or pothole shocks your wrists. It feels like the car is going to vibrate itself apart (passangers don't even notice though b/c it is all transmitted through the wheel). I went down a cobblestone street once... ONCE! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'> If you do a lot of city driving, I don't recommend this - otherwise, it is a decent upgrade, but not the first thing I would do unless the car needs them.
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