"I've heard nothing good about them."

They are the best tire I ever used. I will never use a regular clincher again....now you have heard something good about them.


"Why use what basically is a clincher that you can't fix?"

It's not basicly a clincher. It's basically a tubular that mounts on a clincher rim.


"Since they aren't glued on, they can still roll off,"

I challenge anyone to force and inflated tubular clinch off a rim. They won't.


" you can't ride on them while they are flat,"

Although I have never had a flat with them or have seen anyone get a flat, their literature says you can ride them flat.


"you can't fix them at all if they flat,"

Sealant will fix them. Anything sealant won't fix would still be unrepairable on a clincher tire or tubualr tire.


"they are heavier than a true tubular."

But lighter than a clincher and tube. They are durable enough that you do not have to carry a spare.


You should really check out their web page: http://www.tufonorthamerica.com/whattype.php