Ziggy,
You were pretty hasty to push something on your friend without hearing it yourself, don't you think? All these reviews here are very subjective, but you can still find some continuity in opinion if you study up on a product.
I think the entire mind-set of using harmomnizers is the problem. You nned to set levels, learn techniques, and modify your style to get the most from it. The TC has the best tone I've ever heard, and the parameters for modifying the harmonies are VAST. My guess is that your friend (and ,maybe you too....) thought that a harmonizer was a "magic box" that makes a singer out of any old sound. Not true, my friend. Not true.
I still think TC makes the best sounding boxs in the market, and it's ok if you don't agree, but I'd reeeeeealy suggest that you fiddle with it a bit - it's a complex piece and with a little TLC, it'll perform great.
Give it another try !