The type you want has a few features. First, I recommend billet, because the billet set will have less stretch. They all stretch some at break in, but the billet sets stretch much less. Secondly, a true roller set. That's where the connections between the links really roll independently. Another footnote here. You need to look for rollers that are not split rollers. Those are normally found on the crappy sets parts stores get and all the Chevy guys think adds 100 horse power. You can look at the rollers and see where they have a split. They are just formed right over the pins in the chain. You want full, one piece rollers that are typical on higher end sets. Lastly, I like the sets with nine keyways on the crank gear. Some think that's overkill, but it gives a WIDE selection of where to install the camshaft for best timing, rather than being limited to either one or three keyways.