Ok, I went all science fair on this one.
I took each of my wavelengths and tested for a response within ten seconds. After each test I would drink and gargle with water which would effectively erase any residual sensation.
660- Instant copper, never got too intense.
635- Took a second, never got intense, less of a taste.
594- Didn't really feel anything till right at the end when it started a little.
532 5mw- Nuttin'.
473- Nothing till right at the end then it tingled, but wasn't coppery.
405- tingled more than blue, had no real taste. Buds possibly fried by this point.
68mw 532- Simply hurt after about a second and a half. ;D