Re: $200 kit vs. $600 kit - three times better?
it depends on what you want.
Are you mechanically inclined? Do you like to tinker? Are you ok with mixing 2-stroke oil into your gas before filling up? Do you want a cool mc-looking motor?
If yes to all those, save your money and get a 2-stroke. If no, get a 4-stroke.
Don't be fooled though, the 4-stroke still requires maintenance, just not as much.
If regular maintenance and tuning is done on the 2-strokes, they can last quite some time.
And you can always make the 2 stroke motor quieter. And the 2-stroke will likely have more power.