We have a SpectraLogic Gator attached to our NetApp F740 (with a pair of F740s waiting in the wings) and a SUN E450 running the robotics under NB DC 3.4. It's been running well for the ~2 months it has been in production.
We're doing about 1/2 to 3/4s of a TB in fulls per week (that will reach 1.5TB when we add in the new F740s).
The support from SpectraLogic has been good (we had a few teething problems before we went live).