Original Message

I'd pass on the 520 or a 600. The notar thing isn't really worth it. The fan assembly is complicated and always seems out of balance. Stick with traditional tail rotor. 
if money isn't an object I'd personally go with a 407 if the guy just wants to coast around the ranch and give rides.

ps. MD 900's aren't fast or comfortable the IDS screens and IFC always seem to have problems.