With regard to z-Start function and reliability...
The z-Start has several advantages over the Revloc. First, it requires no changes to your stock clutch. Revloc requires you to send in some of your clutch parts, they are reworked and then sent back. To go back to a stock clutch requires the purchase of new parts. The z-Start requires no changes to pre '04 Husaberg clutches and a simple, reversible change to the '04+ Husaberg clutches that you perform yourself.
The z-Start also has a force limiting feature. The z-Start, when installed and maintained properly, will limit the clamping force into the clutch pack to very near stock levels. The Revloc will keep building force as RPMs rise. Too much force into the clutch pack can prevent the clutch from absorbing shock loads into the driveline which can lead to gear failure.
The downside to this is that the z-Start does require more maintenance. We want to see the z-Start installed within about .010" window to the clutch pack. The "installed gap" is easily adjusted by swapping in thicker/thinner drive plates. Checking the installed gap requires clutch cover removal. We recommend a check within the first hour of riding and thereafter at 25 hours. Most riders can go 100 or more hours of riding time without making an adjustment.
We have more than 2500 units in the field now. Although we have had our fair shair of teething problems, I do not know of a single customer that has had a gear failure with the z-Start.
We also offer a 30-day money back guarantee.