I'm new to Harley's...and trikes. I'm looking at two 2007 Harley trikes. One has the 96 motor with a 6-speed tranny. The other has the 103 motor with a 5-speed tranny. Both are comparably priced and equipped, with around 20K mileage. I will be riding mostly two-up with my wife, at highway (65mph) and interstate (75mph) speeds. Which trike would you choose? Is there a significant difference in power between the two? Any sage advice is appreciated...