The wing has 2 CG marks on each wing when tested showed the CG at being between the marks but closer to the front CG mark. This should be fine if the CG marks are on the correct location. The CG was also check with another instructor at the field by checking the balance on the main spar. As far as the bolts for tightness, there are 2 bolts that can't be reached with a screw driver until you remove both the engine and the muffler. The control surfaces were all checked for freedom of movement and the throws are preset at the factory. There is something strange with this plane in that it would be better suited with a smaller engine or as we have done and change the prop because it just doesn't handle well at higher speeds. There is another Nexstar at our field and in talking with both the owner and the other instructors, they had the same issues. The owner switched to a different prop as well, not the same but close with a pitch of 4 3/4 and he also added nose weight.