I quit, the way the MS Society organized the event made riding 300 miles easy. We had a rest stop every 12 to 15 miles or so, and had food, liquids, bike mechanics, and first aid available at each one. Breakfast was provided at the first rest stop each day. One day's ride was roughly 60 miles (the most we rode was 70; that day we had 5 rest stops. The shortest day was 45 miles, with 3 rest stops, the rest of the rides each had 4 rest stops), then we camped out (they hauled all of our gear to each campground and watched over it until each rider arrived). There were people directing traffic at busy intersections so we hardly ever had to stop and wait, and they routed us on roads which had almost no traffic. There were people who constantly patrolled the route on the lookout for people who needed first aid or help with their bikes. If unable to continue for some reason there was a van that would pick you and your bike up and take you to the next campground. They really took care of us, and our safety was their primary concern.
At night we had entertainment and could explore the town we camped in and go to dinner at a restaurant if the food venders at the campsite didn't appeal to you. I started riding each day between 6 and 6:30 AM, and arrived at the campground around 1 PM, averaging about 14 MPH (many were much faster than me and lots were slower), so I had lots of time to enjoy the towns we camped in.
My bike has a shock absorber in the fork (the stem leading to the handlebars) and in the saddle post. My saddle (seat) was cushioned, but I added another cushioned saddle covering. Then I wore padded riding shorts. Additionally, I have aerobars on my bike so that if I got tired I could lean my arms on them and rest as I rode, so my ride was very comfortable - believe it or not, I did not have a sore butt the whole time, nor sore shoulders from bending over the handlebars. The downside of my bike is that the shocks add a lot of extra weight, making it harder to pedal. My bike weighs in at about 30 pounds. Some people had bikes that weighed 9 pounds, but they are not as comfortable as mine, even though they can ride much faster with their narrower tires and lighter bike frame.
These links will show examples of some recumbent bikes:
http://kmorris.exposuremanager.com/p/128/tram_2404_23_8_13
http://kmorris.exposuremanager.com/p/132/tram_3393_23_8_17
http://kmorris.exposuremanager.com/p/132/tram_3341_23_8_17 This is the only trike I saw, but it is a recumbent.