We need a prescription to get that stuff in Oz, so I haven't tried Viagra. I have wanted to though, because it seems the cool thing to do with Hollywood celebrity types. When I was in Las Vegas this year I tried that stiffnights stuff - it was OK but I probably wouldn't use it again.
It is not what I thought would happen. I figured I would be walking around with a four hour hard-on. However, it only got hard when you are actually in action - it just takes a few minutes to go down, and is ready to go again almost straight away. The best way to describe it is that if you are banging some bird and your mother (or an Indian telemarketer) phones you, you can carry on a 10 minute conversation without losing your boner.