People always laugh, but I was a poor Med student at the time and got a diamond that appraised at $12k for $5.5k, so I say fuck it. You can check their inventory on line and if you see diamond(s) you like, you can contact them and they'll ship it to the local wherehouse so you can check it out in person with no obligation to buy.
I also looked into blue nile and they seemed to have pretty comparable stones, you probably can't go wrong there.
