Although one bow may "fit" a person better than another, the monkey behind it is what makes the difference. Any good archer can shoot most any bow well.
I agree that cost doesn't make a bow. I've shot (and owned) expensive bows that were very nice, and I've shot expensive bows that, to me, weren't worth $5. The adage "you get what you pay for" doesn't always apply to bows.
A friend of mine payed through the nose for a bow that had twisted limbs from the start, and the bowyer won't warranty it. One of the less expensive custom bows on the market has one of the better warranties, and the bowyer stands behind it 100%. 'Course these aren't always the case--point being is check each one out for yourself, and don't accept word of mouth as a guarantee (that's the mistake my friend made).
If you aren't sure, my bet is you'll do better buying used. Some bowyers warranty their bows after they change hands, some don't--you might take that into consideration. At least if you get a bow that doesn't suit you, chances are you can get your money back or close to it vs. taking a 25%-50% loss as is common when selling a bow you bought new.
Good luck,
Chad