That is definitely a good deal, much better than what I've paid for Challenge tires.......Another Challenge tire I've ridden quite a bit is the Parigi-Roubaix open tubular. It's a 260 tpi tire that's 700 x 27c. They ride like a dream with the high tpi and extra width. I've got them on my Jamis Aurora Elite.

I had a similar theory about the inertia of heavy tires when I was riding a 27 incher road bike. I don't know what I did with the excel sheet, but it turns out that as soon as you factor in wind resistance above about 18 mph (depending on rider weight), any rolling inertia you gain from heavier tires is quickly eaten up by drag. Basically heavier tires make you fight the wind more on each pedal stroke than they do maintain linear momentum. Now, on a 7% downhill grade, the weight quickly becomes and advantage. I'll see if I can find the excel sheet. I figured it out when I was waiting for a flight for about 4 hours one day...

For cost-effective tires, the Nashbar Prima Plus 2's do well, as long as their priced ~$10. They're not particularly good in any category, but are a nice balance of ride quality, performance and durability. They'd certainly be a good, cheap training or recreational tires.

EDIT: I do remember that I assumed the rider was a wedge for the purposes of calculating drag, which was probably generous. The actual drag is probably quite a bit more.

I understand the difference, and that nothing will completely duplicate a nice tubular. But most folks ride clinchers these days, and don't want to run tubulars. These "open tubulars," which are the same exact tire as a nice tubular except for the clincher/tubular part, are as close as you can get to a nice tubular on a clincher rim. Click on the Challenge link I provided earlier in the thread. These are not your average clinchers, far from it.

From what I've read since this thread got started is that the open tubulars are great in the road "feel" dept. but don't last very long. Great for racing or fast recreational riding. When I think of tire use for commuting (and I haven't commuted on a bike for years but I have and did for a few years) I think puncture proof and high mileage. I mean unless you are the boss showing up late to work on a regular basis because of tire problems isn't career friendly.

You are correct.

Both my RANS recumbents came with Primo Comets. They are not an expensive tire. In 4 years riding, about 2000 miles a year, I have had 2 "on the road" flats, and about 3 more found at home on pre-ride checks. When I look in tire catalogues, the Comets are cheap and light. So many of the premium tires are quite heavy, especially with kevlar belts. The Comets are thin light and fast and inexpensive. Just saying.

5 flats in 8000 miles might sound good to you but I like my 0 flats in close to 25,000 miles (I really should keep better track of mileage. Basically, I ride about 4-5k miles/year and haven't puncture flatted since the fall of 2004) running high quality, puncture proof tires. My latest choice (the Continentals described above) are very light weight. Not as light as a race tire but lighter than your average training tire.