I've tried the V in regular life as well as while hobbying. I wouldn't recommend it unless you have serious issues ed.
Personally, it takes me a while to come to attention during visits to the mp. Not sure why, probably nervousness. I think too much about it.
Anyway, the V will cause you MAJOR stuffy nose, flushing, sometimes headaches (for hours afterwards), and can really mess with your body. When I first got my prescription, I tried it a few times. It made me hard with just the slightest thought of sex, but once I got soft -- it was almost impossible to bring it back to hard.
Bottom line is, if you don't have ED -- stay away from it. It won't help, the side effects suck, and it could make you actually less hard than if you didn't take it.
My luck while trying it on the hobby was 50/50. One time it helped me be a little more attentive, and the other time it seemed to cause the exact opposite. Stick to the herbal stuff. That stuff does work, but you have to be careful - and they take longer (weeks) until you get much effect.