Some people thought I was a moron to do so, but last weekend I flew from Massachusetts to Phoenix to take the FALANT. I sure don't feel like a moron now that I never have to take another Ishihara plate (standard for FAA medical) test or worry about light signals- I'm among the 50% of folks who pass the FALANT. I can now head full steam into my training, with the end goal of a career in aviation, as opposed to being limited to a private pilot license with restrictions (I imagine that a commercial pilot who can't fly at night probably won't find much work beyond ferrying skydivers or dragging a sign up and down the beach).
My understanding is that failing the light gun test only once deems one permanently 'colorblind' as far as the FAA and your hopes of flying commercially are concerned. Failing the FALANT does nothing to your record and you could still take the light gun test if you fail it. I've also heard of some variables that exist for the light gun test. The FALANT is done in a room with seemingly controlled lighting conditions.
If you have a color deficiency and you're serious about getting into aviation, I highly recommend a trip out to visit our very own My Fight Surgeon in Phoenix and taking the FALANT. I was in and out in about ten minutes, and the office was about a 10 minute cab ride from the airport. There and back in the same day. Cost me a few hundred bucks to fly there, but it was well worth it. The test was only $50 bucks.
If you can find a FALANT closer to home, go for it, but I couldn't. The Coast Guard Academy apparently has one, but they didn't want to help.
The Doc didn't put me up to this little sales pitch here, honest. I'm just happy to have a huge weight off my shoulders, enabling me to move forward. If you have a problem with a mild color deficiency like I had, go out to Phoenix and see the Doc. Nice guy, too.