I was in a Fender based Facebook group and one of the admins heavily pedaled snake oil caps, cloth covered wired, that whole deal. I posted data that disputed their claims, without being derogatory, rude or combative, and got my comments/info deleted, kicked and blocked from the group, merely for posting data. Yes, some people really are that easily fooled and they even ignore evidence when presented with it. I've learned to stop wasting my time on those people. If you're willing to learn and not have a personal bias, you will quickly learn what's snake oil and what's real. This particular situation, on FB, just kind of erked me, because this individual is slinging snake oil, misinformation, and on top of all that, he claims to do tech work and mod people's guitars. He actually charges people to put in cloth wire and oil caps, and claims huge improvements. That makes me kind of sick, knowing the truth, and also doing tech work myself. I dont like seeing people who dont know better, get ripped off by someone they look up to and expect to have real knowledge on the subject. No one should pay massive marked up prices for wire that does nothing and a cap that uses outdated technology and inferior materials. The only reason to choose a different cap in your guitar is if you're changing the component value to adjust the filter, or if you're really anal about having the most consistent tone possible, you can put in more stable cap compositions, which will drift less in different weather conditions.(PIO would be one of the worst choices, for this btw..) If you want to talk about guitar amps, I could talk about the difference is cap composition all day. In a guitar the composition is negligible if you're comparing two caps with the exact same measured value. I'd gladly change my stance if any real significant data can be shown proving otherwise.