Re: Spraque Vitamin Q vs Bumblebee. Any difference
I definitely agree with the above – its the capacitance of the capacitor, not the material that is creating the capacitance, that matters.
If you want to make everything perfectly vintage spec because that's part of your hobby and doing so interests you, then go ahead. If you're concerned about your tone, rather than the "accuracy" of your specs, then don't worry about the material
There are probably others here who know more physics than I do who can explain the details (I have a bachelor's in it, but my grad degrees are in other stuff), but I would bet that if they exist, the audible tonal differences between materials would hardly be noticeable, would wash out when you factor in the tolerances for each type of capacitor anyway, and / or would be primarily psychological.
I bought one of these big ol' boxes of caps from Amazon a while ago, and it has opened up many different tonal options by letting me explore various values for both treble and bass cutting:
https://www.amazon.com/gp/product/B07117K2ND/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
I'm in no way affiliated with the above, and there are probably tons of other boxes 'o caps that you an buy with values that are roughly where you want your guitars caps
MC