The G200 does use more runway, but I would say it is not significant compared to many other aircraft.
Facts -
G200 6000ft runway sea level. You can go Max weight anywhere.
The G200 crew I spoke to said 6000ft they fly a 2200 mile trip with reserves with 6 people. KSAN - KBTV. and they also do KSAN - PHNL.
I will say the two big things the G200 has going for it is.
1. Cabin size. It is a huge cabin for what the plane is and buyers see that.
2. Price - For the cabin size and range the price of the G200 is a great value. A 2008 just sold for less then 4 and change. I was told you can get a late model for around 1.5 now.
I do not think you can beat that price for the value.
Maintenance on the plane is not bad from what I have seen.
I'm not expert or even a novice on the Legacy, but once again I know a crew that flys one.
Compared to the G200 I would say all it has going for it is cabin size. Performance is not that great and has limits on runway etc like the G200.