Jerry,
In spite of what apers to be laborious technique, decent tubies (except things like Condors--yech) give one a feel for the road like nothig else.
I cannot speak to performance on bikes made of modern materials, but a classic steel road frame with decent wheels and sew-ups is a dream. Plus, it is very quick and easy to change a flat--faster than a clincher.
And the really weird thing is now they are cheaper. I am presently riding Vittoria Competition Rally 21mm tires. They only cost 16.95 at my local bike emporium. They DO NOT ride like a cheap tire--they popped on nice and straight, and so far have proved their Kevlar mettle on nasty city streets. They have one piece valves, but at that price they are disposable! (I don't even really mind fixing good tires--it used to be something of a cult badge of honor ;-)) Decent clinchers will run 25.00+ for the tire and another 5 for a tube. This is 180 degrees of what the situation was even 10 or 12 years ago.
My 2cents, but I'll take sew-ups for my good bike any day. And I have never found gluing to be especially difficuly.
Hope this helps,
Jackie