I'd do it.

I have been up to the top of the Stratosphere Tower in Vegas. It made my stomach feel a little funny, but I did it, twice.

That being said, I seem to be ok with large, secure man-made objects like that. I don't mind dams, bridges, towers, etc. I'd go on the Grand Canyon overlook, too.

However, I HATE heights that don't have to guardrails, like the edge of a cliff, a roof, etc. Guess I just need that sense of security.