For Mars, I've found the IR blocking filter is essential, otherwise the blue channel appears to have some light leaked into it from other wavelengths. At least that's how it looks when I split it into separate RGB channels.
See my tests
in this thread.
And as RB said, a good quality one is essential. The baader seems to be quite good, and at only $80 is good value.
I don't know if you're strictly talking for imaging or visual, but Dave47Tuc used a red filter for Mars, and at times a light blue as well. Both appeared to bring out some good detail in the image that was otherwise washed out by the brightness. But like all planetary observing, the best detail was brought out by just waiting, and looking, and waiting, and looking. Your eye will adapt to the brightness and when moments of good seeing come, the detail jumps out at you.
The best view I had of the night was in Geoff's scope when his pentax was fogged up and it dimmed the planet enough that detail was jumping out at me.. ignoring the bright halo around the planet because of the dew, it was a simply stunning view when the seeing was great.
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