the best caps are the paper and oil ones with out a doubt they do make a difference.
PIO caps have very closer tolerance than ceramic ones (specially the cheap ones). Other than that there's still no _scientific_ evidence that the cap's composition has any effect on tone in a passive guitar electronic - which doesn't mean there is no difference at all, but I really doubt I'd notice it on a proper blind test (which means find a set of caps of different types with perfectly matching values).
This being said I do use PIOs on all my guitars (with 50s wiring - which is scientifically proven to make difference but that doesn't imply it's "better" neither) and I'm very pleased with the result ;)
@Lucas:
Llong shaft pots for a LP yes, if in doubt open your guitar and checkout what you have in it. The tone pot's value is less important than the volume one's so don't overthink it, any log pot in the 500K range will do.
More generally : don't waste too much time looking for "the best options", as there's no such thing in the whole universe. At most, you may find out what are "possibly the best options for you for a given guitar, a given amp, a given project, at some point in your life, as far as you can tell" - and this requires quite some hands-on experience you obviously don't have yet. Quality is a relative concept. Ok, there is some "absolute" technical concept of quality (ie for pots being robust, having a consistent taper and being as close as possible to their nominal value), but most of the aftermarket guitar pots out there are at least good enough. Then there's the subjective, personal tastes part - some people will prefer a quite stiff pot, some a very loose one, some people will prefer a steep taper (like the BKP custom CTS) some a much smoother taper (and some will even prefer a linear pot, with pretty good reasons). Until you try and find out by yourself what difference it makes *and if you like it*, you just won't know what is "the best" option for you now.
Oh and yes: on the net, uppercase == shouting...