I'm considering purchasing a 52in. Huslter FasTrak. But now I need to decide if I should go with the 18hp or 20hp model. Considerations: 1) Mowing approx. 1.5 acre, flat. 2) It's going to have a 230 lb. load, namely me. Does that matter? 3) Can I pull a roller with the FasTrak? If so, should that make a big difference in my decision on which engine? 4) Will the 20hp last longer than the 18hp, all other things being equal? In a nutshell, is the price difference worth it? Thanks for the replies. Go_Tribe.