Just wanted to chime in since I have Koni adjustables.
http://www.ft86club.com/forums/showthread.php?p=1487005
They have been really great for me and I don't think you are giving up any quality by going with the koni. That being said, I have heard nothing but good things regarding bilstein as well.
The adjustability of the konis is pretty cool. Yes, you end up mostly using 1 setting, but like I said in my thread, it does a lot more than you think. Personally, I really enjoyed dialing in the rebound and having a "different" feeling car once in a while. Hopefully this helps!