What is the difference between the John Deere 6120EH and 6M 125?

Here is how the John Deere 6120EH and John Deere 6M 125 compare on John Deere's published specifications:

• Horsepower: John Deere 6120EH 120 hp vs John Deere 6M 125 123 hp
• Pto horsepower: John Deere 6120EH 102 hp vs John Deere 6M 125 97 hp
• Weight: John Deere 6120EH 9410 lb. vs John Deere 6M 125 13779 lb.
• Fuel capacity: John Deere 6120EH 44.4 gal. vs John Deere 6M 125 46.2 gal.