The Buick chains are just loose to begin with, thus the need for the tensioner. Make sure you have a good tensioner, for one.
Ive used a double roller and had no problems that I could tell, however that was before I started racing the car alot. The last time I had the front cover off I put in a stock GM timing chain set w/ a new tensioner.
Ive heard pro/cons about the double rollers, like I said, I had no problem with mine. Just make sure you DONT use the tensioner with it if you go with a double roller. As far as the stocker (from GM) you know theyre good for over 100,000 miles at least, and I have learned that the nylon cam gear is better to have than the metal. I know everyone (including myself) would usually say metal is best, but its something to do with false knock that can transcend through the cam with the metal gear back to the knock sensor, where as the nylon one will deaden the sound and is much quieter. I know some might go against this, but this is just what I have heard from a couple of sources, including reputable Buick/TR people that have been dealing with them since they came off the assembly line. I did notice the engine a bit quieter from the front with the new GM chain versus the double roller, but as far as a performance difference, I cant say for sure.
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