I don't have a good computer audio setup, and frankly it's not high on my list of priorities, so at this point I'm happy with CDs and LPs. I have about 400 CDs, and with a wife and two kids to support on one income, I'm very picky about what I buy. If I want to experiment with music I'm not sure about, I'd rather do so in a live setting because it's more likely that I'll enjoy it that way. When I see a band whose performance I really like, I usually don't buy their CD, because I'll probably never listen to it - I guess I've been through enough musical epiphanies for one lifetime (though I'm sure I'll get surprised again one day), and now I just know what I like.
With LPs, I follow two strategies: firstly, I try to buy my favourite albums new on vinyl rather than CD if I can. Secondly, I buy anything second-hand that catches my interest, as long as it's really cheap. My goal is to be able to DJ house parties with old vinyl, even if I never listen to the LPs at home, and that requires quantity. My collection is still in its infancy though, with ~250 records.