I have an old school JT Spectra with double thermal lens AND the Vortex fan and never have a fogging problem. I don't run the fan all the time though. I turn it on for about 30 seconds when I put the mask on to equalize the air temperatures and then only turn it on for 15-30 seconds at a time when playing if I start to fog up.

So I say YES, for the most part, fans are worth the money and noise.

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