Good choice of tires. :thumb: But for racing the Ultimo are the ones that are much lighter. Not as much flat protection, almost none, but they roll well and are light, 165 grams. That is about 75 grams per tire less than a gatorskin. You just put them on to race or have them mounted to a second set of wheels. Take them off after a race. Yes it can be a pain if cost is a consideration. But racing tires don't last long in daily use at least in my experience. But then tires cut or get a damaged side wall well before wearing out 9 out of 10 times for me. :(

Gatorskin , a Continental Tire feature is a sidewall reinforcing mesh..
Puncture resistance Tread belts are a separate feature.

ironically, the bad reviews on gatorskins was due to its weaker sidewalls. My friend's gatorskin got pulverized by his cat, which he sent back to the shelter for what it did.

Kevlar isn't "stiff", it is very flexible. It has low elongation, meaning it doesn't stretch much before breaking.

What weakens it over time is not the load applied, but the bending it undergoes.
With kevlar bulletproof vests, the common (USA) police procedure is to replace a vest after two years if it is worn daily.
http://answers.yahoo.com/question/in...8004005AA1g70w

You should have done a little more research. It can take over 3 weeks to receive your order since they ship from the UK. They'll reship if you haven't received them in 28 days. There's no tracking available with the free shipping to the US.

To be honest I have had some problems with Ultra Gatorskin sidewalls. The other thing is they shed strings that tend to collect in the hub and cassette. Still they are pretty good tires and are consistent in their quality.

tough tire
 

Gator Hardshells are Gatorskins with extra sidewall protection. I can't tell the difference in rideability. Hard and fast.

Schwalbe Marathon Plus are about as bombproof as it gets, but heavy and sluggish.