I agree with you about Lima. Its cool, but its like a lot of big cities in that once you've seen the major tourist things, you feel satisfied and want to move on. I loved my stay there and would tell anyone to go for a few days, but I can't say that I'm itching to go back. Cuzco, on the other hand, I would love to tour.
Are you telling me that pisco sours are so delicious that you would drink one knowing it was going to make you ill? Because I need to try one if that's the case...
That said, I can't say why I haven't bought it here. You know how there's something about place that adds to experience. I think that's it. I don't want to ruin the memory if, in fact, the taste isn't as good as I remember (if that makes any sense).
I had one of my favorite ever moments while in Peru, it was amazing: http://hubski.com/pub?id=1779