Well, I decided that I can afford to spend the extra on a Stihl instead, so I am wondering a few things about them. Right now, I am looking at the new 430, the 500, 550, and the big 600. Now, the problem is, why is the 500 more then 550? I know the 600 is the top of the line one. Is the 550 being phased out? Why is it 30 dollars cheaper then the 500? The 430 is supposed to be a stratocharged 2 stoke, but how does it compare to a 4 mix?