Just want to clarify things here. Fluidampr indeed revised their design, and their new harmonic balancers should work perfectly with the OEM bolts. Unfortunately things like this are one of those parts that can easily sit on a shelf for a few years, so it sounds like you got one of the old versions, Alex.

The reason I bring this up is that when I bought my Fluidampr, I got the longer bolts with it and, being the idiot I can often be, installed it without checking. A couple days later, my balancer seemed loose, so I tightened the bolts. This caused my crank sprocket to fracture. The longer bolts, if used with a revised balancer, do not have enough threads on them, and the shoulder will poke out past the balancer, preventing you from being able to fully tighten them down.

Long story short: Some Fluidamprs have a thicker-than-OEM hub, some do not. Don't repeat my stupidity; check before installing.