I put these in a 2016 Chinese made Epiphone Casino. At the same time I also replaced the stock P90s with a set of Lollar P90s. Wiring was done classic Gibson 50s style. For sure the pickups made a difference. But it was clear that also the pots made a difference.
The old pots were around 490k ohm. So not far from 500k. But after I installed these 550k pots it is clear that they introduce a lot more treble frequencies in the guitar. Big difference. Unfortunately, it introduced so much treble frequencies that I am considering taking them out and replacing them with normal 500k pots. For fingerpicking these pots are great since fingerpicking anyway removes some high treble content. But playing these 550k pots with a pick leads to a shrill, thinner and harsher sound. If you wanna stand out in the band mix, then maybe. But for playing at home I have my doubts. The stock Epiphone P90s are missing a lot of treble, so also here these 550k pots might work. But not with Lollar or Gibson p90s.
One funny thing with these pots is also that the volume response changed completely. I normally play my guitars (humbuckers) with the volume turned down to maybe 7 on the neck pickup and at 9 on the bridge pickup. But with these 550k pots the guitar is almost silent at 7 on the volume pot. All the difference is between 9 and 10. In conclusion, these pots are only for guitar + amp combos where a lot of treble is missing. These 550k pots are like playing with a treble booster constantly on.
