Tires are another one of those topics like saddles. Its a personal preference. But here are my thoughts. I weigh over 200#. Clydesdales can destroy tires in a short time. I’ve gotten less than 750 miles out of a set. So I have gone through allot of tires searching for durability and ride ability. I have road on all tires mentioned on this forum. Sheldon Brown explains it best on his tire page, Sheldon Tire Brown .
The RAGBRAI bike shops like to replace tires with Conty Gatorskins. This is because they are high price and they please the customer. Conty Gatorskins are an excellent durable tire. It performs well. So I do recommend this tire. I just dont like the price. Tires like Conty GP4000 are clincher race tires. This tire is designed for speed not longevity. They’re light which means a high thread count thin sidewalls and tread tire. To get high thread count. The threads have to have a more narrow diameter. This make the walls thinner. Thinner wall are more puncture prone. They flex more in cornering. Which can cause a bead to pop. Personally I use Conty Ultra Sports and Hutchinson Equinox tires. They are about half the money as Gatorskins and GP4000’s. Training/sport tour tires like the Conty Ultra Sport and Hutchinson Equinox have lower thread count and thicker treads. The sidewalls are thicker and stiffer. Overall training tires trade durability at the expense of weight/purformance. For racers while training, a lower cost, high mileage training tire is desirable. For recreational/tour riding. Sport tour and commuter tires are desirable. These tires have lows thread count, thick walled and tread. They also have a bit more tread pattern to them. This is to have some grip if you get on to a soft surface. You will find on most road race an training tires. The center of the tire tread is slick. Little to no groves. This is to give maximum road contact. Sheldon Brown explains tread pattens and there uses.
Iowa has an excellent road system. Which allows RAGBRAI to switch routes to see our beautiful state. State, county, and local municipalities go over the roads and either mark or fix bad spots. You will even see patrol officers with brooms. Brushing gravel off the intersections at times. So overall road conditions are good. But riding in mass. You sometimes cant avoid obsticals. So you want sidewalls that can take a hit. I would not go with a racing tire because they are prone to pinch flats. You will hit holes, tracks, and cracks. So a thicker sidewall will give you some extra insurance. Because of my weight I also run at a higher pressure. This will give you some extra safety against pinch flats. Makes the tire roll a bit faster. But it also give a harsher ride. So again another trade off. What ever tire you choose. Making sure you top off the tire in the morning before you leave. That will go a long way to keeping you from flatting a tire. Soft tires are very prone to pinch flats no matter the quality. Most bike tires will lose 10%-30% of there air in a 24hr period. So pump them up in the morning. On a long day. Check them at the meeting town.
I would not recommend using any sealer’s. When you have to change a tire. Its a freaking mess. You want to pi$$ off a bike mechanic fast. Give him a tire to fix with that crap in it. Carry tire tools. Spare inner tube and repair kit. Learn how to apply a vulcanised patch. Also remember adding any rotational weight to a wheel greatly decreases its performance.