We used Justfares a number of times from 2000-2002 -- they did have some amazing deals. After that, they usually were unable to deliver on the prices advertised on their website, or didn't respond at all. I assumed they had gone out of business, and I deleted the site from my bookmarks a few years ago. If their prices are significantly better than the competition's, and if you can pay by credit card, I wouldn't hesitate to use them.

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