Gary at Brison knows what he's talking about when it comes to lubing his engines. He prefers that you use a synthetic from the beginning. As far as the break in taking longer, there's absolutely no harm in that at all. Break it in like you're going to use it, there's no benefit in running rich in the beginning with a gasser. The stuff we fly has to be absolutely dependable for many hours out of sight at a time, and we fire em up and send them out brand spanking new with the needles fully adjusted from spark one. Believe that we run them harder than you ever will[8D], and we use quite a few of the same size and types of engines.