From years of looking at different audio stuff... I have come to the conclusion that parts means nothing without a proper audition. If you want some extreme examples, check out FM Acoustics. Their parts are simply CHEAP, your everyday industrial parts. NOTHING SPECIAL AT ALL, except for the actual performance it delivers, which is way outta the world, and they priced it way outta the world too.
Not to mention, each type of cap have its place, using all solid might end up with a thin/sharp signature in the sound that is not at all pleasent to listen to.
upon closer inspection of the cap, it is SMD electrolytics. It doesn't even show who made those caps... It is just some plain industrial stuff...