Danny is Danny, at least we learn something from what he is saying, get a better understanding on how speakers work.
Almost every speaker I have torn into has had cheap, or really cheap crossover parts. Even some more expensive speakers still have crap parts in them. These will sound better with better parts. Even changing the sand cast resistors for higher quality ones will have a affect on sound.
High quality parts are stupid expensive, and sometimes HUGE. Will a $2000 speaker sounds better with a $2000 crossover? yes, it will, but is it worth it?
With old speakers that caps have drifted, or going bad, just about any cap replacement will sound much better. You can do a full recap on a pair of speaker for under $100 the before/after will be huge!
Sonic Caps are good, but they are bright, sometimes harsh, can be clinical. Not all vintage speakers respond to these kind of caps well. They can loose their warmth, smoothness. IMHO, I will not use them in the tweeter circuit. They can make good speakers become fatigueing speakers.