I own an MS250 and I agree with the previous posts. I would emphasize the difference a muffler mod makes. I took mine apart and opened up the baffle, but you may not have to get so in depth to notice a big gain. There is a very small outlet hole in the MS250 muffler. I think you could just open that hole and take a screwdriver and open up the louvers it would help a lot. Obviously remove the limiters on the carb screws and retune. I also run Stihl full chisel chain and I feel that makes a big difference also, although there are a lot of different opinions on that. In short, it's not worth making a change unless you move up to a pro saw. These simple mods made a more noticeable difference on my MS250 than on any of my other saws. The louder muffler also makes it easier to tune. IMO