I used the shiny bolts, bought them at auto zone. Then when they either came loose or whatever they broke off at the heads and sent my pulley flying off the crank. I got the balancer off and tried to drill out the old bolts but it was too much of a pain in my *** so I got another balancer. I am 99% sure that I went to a hardware store and bought grade 8 bolts this time around, I also used a little bit of blue loc-tite (vibration resistant) on the bolts to keep them from walking loose after a while.
I don't know whether the cheaper bolts just broke from the stress, or had been walking loose over time causing a wobble. I think they were walking loose because I had a noise down there the day before this happened. I changed my oil and looked but couldn't see anything loose. I SHOULD have checked the bolts on that pulley but I didn't. Next day on the way home from work it snaps off and throws the belts. Luckily my pulley was laying on the front sway bar and the belt serp belt didn't slice through the hoses. I did however loose the jackshaft belt, never found it. I replaced the belt, new balancer, and grade 8 bolts, put it back on, and have been trouble free for over a year now.
The cheap bolts I had in there only lasted about 6 months. I'm 99% sure they walked out, but for a few dollars more, get the stronger bolts.