I bought just the one - I believe it's a "medium", but it's the heaviest thing I've ever used, heavier than the free BKP picks.
After an initial honeymoon of a week or so, I stopped using it regularly and found I liked the BKP free ones. So I ordered a stack of slightly less heavy (than the free ones) BKP picks.
I now use three types of pick depending on the guitar and tone required:
1. Dunlop nylon. Grey things, .88 I think. These have been my stock picks for years and years, and I've come back to them in the last couple of months. They give me my required amount of attack and I find them the most expressive for the way I vary picking. They take quite a while to wear as well. If I were to go gigging, these would still be what I want taped to my mic stand...
2. BKP picks. When I want a "tortoiseshell" type of pick. Sometimes this is my go-to pick at the moment (especially on the "guitar-that-shall-not-be-named" :lol:). I get roughly the same sort of effect out of them as nylon picks. I wouldn't be upset if I turned up to a gig with only these. The big downside for me is that I wear them down quite quickly (both heavy and medium) and I find they wear unevenly for me - I get little scooped patches appearing with sharp edges.
3. The Red Bear. I do like this pick - I seem to reach for it when I want a "luxury" mellow feel. I couldn't gig with it though - doesn't seem to have any attack at all in my hands, even on the "guitar-that-shall-not-be-named", which is where I probably use it most. My chug- or shuffle- rhythm playing on a crunch tone just does not have the bite to cut through a mix with this pick. And... it does wear down :o - it is definitely not a "pick for life" when I use it :lol:. However, the wear is very even and the pick is going to usable for quite some time (years at this rate) if I don't lose it. I must admit though, if I found the tone/attack more usable for my own application, then I would regard it as cost-effective when compared, say, to the BKP picks.
On clips I've done recently, I have used all three picks during over-dubs to obtain different tones with the same guitar and amp settings.
Hope that helps! I'd say give one a go...
(Notice how I managed to avoid saying "tele" in all of that... D'OH! :lol:)