I pull a 10 foot wheel disc, a Bush Hog brand, behind a 45 HP New Holland TC45A. Use it to disc the garden, not running it down to the axles, but the tractor handles it okay. How one of these compact tractors will do what you wan it to has more to do with the tractor weight and the traction it's getting than the HP. Mine has the industrial type tires instead of the agricultural, which I would prefer, but I have fluid in the rears which really helps.
