Any converter properly built is fine for what you are doing. Notice I said properly built/remanufactured. As long as you have the correct stall speed for your application my only suggestion is to add a smaller cooler since you are hauling. Keep the trans fluid around 180-190 degrees (using a quality fluid like ATF + 4) will help durability of the trans and fuel consumption. I doubt you drive this rig when super cold outside - if you do, bypass the cooler for this cold weather operation or run the outlet line from the trans to the radiator first then the cooler.