Bought a 1995 220 Celebrity 5.0L that had the lower unit knocked off. It had a DP-E Duo Prop lower gear units (Ratio 1:95) I am finding I can find a complete single drive unit for 1/2 the price of just buying a lower duo unit. What are the draw backs of just buying a complete single drive. I know less thrust but so what for double the price. It practically totals the boat to buy it.