Good buy, or not?

My latest DealExtreme order also contained a bunch of these: 0.3mm Metal Guitar Picks (24-Piece)
They we’re only a couple of bucks so I thought why not, let’s give it a shot. And I actually like them. These picks add a slight bit of high to my guitar sound and they give me some more control. But they’re metal picks so they’re pretty ruthless. Ruthless yes. Yesterday during rehearsal I spent more time replacing strings than actually rehearsing. One string after the other simply snapped. So with respect to string wear these picks are apparently not such a good buy.

Good buy, or not?