This is a much tougher choice than comparing Wade to Capriati. Davenport is one of the best ball strikers in the games history, and I would say she hit a cleaner ball than Wade. Wade though was overall a better athlete and mover than Lindsay was I think, so in my opinion those things sort of balance each other out. Davenport spent 90-something weeks as the number 1 player in the world, but Wade in my opinion had tougher competition during her prime years than Davenport did during hers.
In comparing the slams, Davenport won all 3 of hers in a 3 year span, while Wade's last was 9 years after her first. So you could argue for Wade's longevity as well as the fact she won all 3 slam finals she played. They won the same 3 slams, so no way to argue relative importance. Davenport did however make it to the French Open Semi's..Wade was never able to, although again field quality could be used to explain that. Its kind of funny though, not only did they win the same 3 slams, they each won 55 singles titles if my count is right.
In the end...I gave it to Davenport by a hair. I did so because she made more slam finals than Wade did, achieved the number 1 ranking, and in my opinion was slightly more competitve against her contemporaries than Wade was. They are extremely close though, depending upon how you look at it. You could just as easily say Wade because she had tougher competition, but Davenport's achievements in my opinion slightly outweigh that.