The Capacitor its quite easy to install as any opther capacitor, yet the thing to have in mind its the size of it. For most guitars, you might need to have it installed on a mini-potentiometer or installe strategically on the side of the pot that dont crash of touch the sides or walls from the guitar cavity.
As this is supposed to be installed on a Tone Pot, end tone pots are usually on the lower part of the guitar and the cavity its smaller, you might want to have this about the minipot and space distribution with this cap in advance.
If its for a Tele, you will have no problem as there is a bit more space, But stratocasters might be a bit a thing to consider befor soldering and trying.
Sound: The capacitor filters the high end sounds quite good, yet it doesnt guive you a very mudy sound, more like music being played on the next room type of sound.
I like it, but the tone its a personal preference thing, therefor i can suggest you that for this price, you can try it and check.
Personal recomendation: Thomann has the same Capacitor but in smaller size. That one will do the same trick ;)