[PvK]

It makes them more interesting and yes it gives more of a chance you'll lose them for someone else to take back. It's not certain they will, though. Give them to someone tough so they can hold onto them. The Chalice is wonderful for curing afflictions - it'd be worthwhile even if the knights came regularly - I've had one for a half-dozen turns or so and haven't had any knights arrive. It's held by the best hero in the world, so I'm expecting he'll have a good chance against challenging knights. Some of the unique items don't mention their drawbacks in their descriptions. In general though, my feeling is that they are powerful enough items that it's good they have a drawback, and since they need to be lost for anyone else to use them, it's also good they have a drawback and a mechanism for losing them built-in. Makes them more interesting and fun, IMO, too. There are some though that I would only use with the appropriate type of hero and/or against the appropriate type of foe, though, but again, I'd say that's a very good thing both for balance and for interestingness.

PvK