The value of the tone cap is basically inaudible with the tone control set on 10. You can use different value tone capacitors in conjunction with say a 500k pot, and with the tone on 10, you wouldn't hear any difference in the sound. There might be a 0.1dB difference in the higher frequencies that you could measure with a scope, but not enough for the ear to differentiate.

However the resistance value of the tone pot does make a much bigger difference, and you'll certainly hear a difference between a 500k tone pot and a 250k tone pot, with the 250k pot giving a darker tone in any given circuit. Taking the tone pot and cap out of circuit altogether can certainly give a very noticeable extra brightness to the sound - hence the popularity of 'no load' tone pots that do this. The Fender TBX circuit basically provides a variable extra resistance when taken above a 5.5 setting by dialling in more resistance in conjunction with a treble bleed cap, and turned full up you get an equivalent brightness to a no-load pot - but the treble gain is obviously more controllable than the on/off gain a no-load pot gives.

The lower the resistance of the tone pot, the more likely you are to hear slight changes in the tone capacitor value when the tone is set to 10, but at 500k and 250k, you really won't notice any effect until the tone pot gets turned down a bit.

250k vs 500k volume pots also make a difference to the tone, as anything in the guitar circuitry is forming a resonant low-pass filter circuit with the resistance, inductance and capacitance of the pickups (and also the input impedance of the amp), and the pot values affect the cut-off values of the filter. The higher the pot value, the higher the cut-off point and resonant peak of the resultant filter circuit is, so the brighter the pickup sounds. The position of the resonant peak can also play a big part in emphasizing any excessive treble or mids that the pickup naturally has on its own.