Nitro wing,
I've had a couple of their yaks and think they fly great. However there is a coule of small mods you might consider. First, put some triangle stock between the cowl monting tabs and the bulkhead. The tabs tend to wiggle loose after a coule of flights... at least on the yak... Second, put some small screws into the firewall from the sides of the motor box. I yanked my firewall completely out once...on the yak but the constuction is nearly identical so it really can't hurt...