The john deere compact tractor 3120 is 30.5 hp and 28.5 at the PTO. I currently have a 5' bush hog that it seems to spin fine. I have 30 arces to cut soon and the 5' is SLOW, thats why I want a 6' but afraid my tractor may be underpowered...anyone have an idea if it will work? JD dealer says it will be "marginal" and sugests I buy a bigger tractor! (which I cant afford). Thanks in advance!