Real Green is the real deal.
It is expensive...but so is a ride on and I WOULDN'T run my business without it!
Just finished my first year with it and it is great...and I probalby don't even use 20% of the program.
Most of it is WAY over my head, but there if I ever need it (or hire someone smart enough that understands it).
I am sure there are other programs out there...but Real Green covers everthing and it has and still is being designed by a guy that owns a lawncare company.