I am having the same exact issue with my Lanier Razor 3D. Even on low rates, it will snap out hard to the right. I've played around with the CG and it makes no difference. It balances laterally, but out of curiousity, I tried adding a half ounce of lead to the left wingtip with no change. I even tried adding elevator differential between the halves (which made it very interesting to fly) with no affect on the snapping out. I'm about ready to give up and strip the airframe. I bought this model used and it was in pretty bad shape. I had to replace the firewall among a few other things. I'm wondering if it could be related, atleast partially, to a wacky thrustline. I'm wondering what else I can try/check before I toss the airframe.. FWIW, I'm running a Saito .82 w/ APC 14x4W prop.