I have the same combination with the saito .82 and a 14x4 prop also used a 13x6 a couple of times. and mine does the same thing, not quite a snap but more like a roll to the right. In 4 months of flying this plane I found that it does not roll out when inverted. Examined and measured elevator travel and have them exactly the same and still does it. Have travel set a little under 5/8" of travel. Contacted ultra and they told me to keep dialing in less travel till it goes away. Finally caught me out last saturday and because of not enough travel went in inverted. One thing I'd like to say though is that the plane does awesome knife edges and does great IMAC sequences. But if you cant trust it it will eventually bite you. Its a shame I really liked this plane but because of this behavior i wont be getting another one.