When it comes to the different Flashes, I definitely have a favorite.
Wally's story was (key word there) one of the most interesting in comics. His own series started out with him being an uninteresting jerk (drawn statue-still most of the time), but it was quickly rescued by two sorely under-appreciated Flash contributors: Writer Bill Messner-Loebs and artist Greg Laroque. Loebs fleshed out the unlikable jerk, giving him sympathetic reasons for the way he sometimes acted, and allowing him to grow as a character. And Laroque brought a wonderfully lyrical line and lightness of touch that made the figures dance across the page. In issue 50 of their run, Wally got this new costume, in a great coming-into-his-own story that was one of my first favorite comic books.
Mark Waid took over for Loebs, and took the coming-into-his-own thing to the max with the outstanding "Return of Barry Allen" storyline. Ringo took over art chores soon after, and the character became one of the best in comics. He was humble, very much aware of his past mistakes, and yet he had transcended them to achieve his full potential. It made for a great every-man hero, and Waid kept the light and humorous side that Loebs had established. About 100 issues of great comics all told, and well worth digging through the back issue bins for.
Then... everything went downhill. The book floundered for awhile; Geoff Johns made it popular again, but with a brooding and joyless Wally that was never as fun to read as the "good old days" stuff. Johns either didn't get what made Wally work, or didn't like it. His version supplanted seriousness for maturity, and the magic was gone. And, just to pour salt in the wound, the awesome costume that was distinctively Wally's gradually got watered down to be basically the old version, as various artists stopped bothering to draw it correctly. It wasn't even a story element, just apathetic editing.
And then, Dan Didio did everything he could to erase Wally from the DCU. He gets sent to the future so Bart can be Flash for awhile, which is such a disaster that it only lasts 13 issues. Then Wally is back again for 10 minutes or so before Barry Allen is resurrected. It takes DC another 10 minutes to figure out that Barry Allen is a pretty boring and one-dimensional character by contemporary standards, so they have Johns retcon him in an interesting past. Wally, meanwhile, whose powers arguably exceed Barry's, and whose life is far more interesting, is immediately shunted down to B-list status. Until, that is, Flashpoint erases his existence entirely. Can you guess how I feel about that?
Anyway, if you waded through that long rant, here's a little tribute to the Flash; not the first or last, but the best of them.