Guys, don't play with the crossovers. I have been in touch on this subject with Richard a lot over the last few months. He's building my Quatro's as most know and I have asked about 'component upgrades' in the cross over. He listens to nearly everything on the market regardless of cost to see if he can make things better. He constantly tweeks as we all know. Most often he doesn't even talk about it or discuss it, he just makes little upgrades to things. Most designers do this. I just sent my amp back to have the internal crossover installed and they upgraded a few things. Can't wait to get it all in the house and set up...
Anyways, Richard choses components based on sound and not cost. I know a couple of guys who like to tinker and they upgraded caps to Mudorf's and ruined the sound. They went back to the less expensive caps that were OEM.
Richard is one of the top speaker designers of all time. There is a reason for that. You may think he's making concessions in the lower priced speakers and that you can make them better. Maybe to someone's ears they are better, but they aren't what Richard feel is better sound. Folks give him crap for using his barrier strips for connection too, but he actually has auditioned other connections from Cardas to WBT. He choses what he feel is best.
I speak often to a DAC designer and he offers folks the options of different caps (they seem to matter the most to the sound at this level). He loves Mundorf's for their open sound and offering a huge soundstage, but feels they aren't as warm sounding in his DAC's. They cost a lot more than the other cap upgrades, but most seem to like the warmer sound of the other upgraded caps (Black cat I think they call them). Both the upgraded caps are better than his stock caps, but even the stock caps sound great and the price difference just isn't worth it for many as it's hundreds more.
Good luck playing as some just can't help themselves and I respect that. I used to play with speakers many years ago and I always liked what I did better than stock until I spent a lot of time with the upgraded speakers and then switched back to hear the differences. Often times in audio or life you don't know what you have until you no longer have it
....Just sharing the 'other side' of things.
Please post your thoughts on any upgrades you make though as they may just be better to your ears. Using top end components can make a big difference in sound in many products. Just look at the Aesthetix's signature line. Just upgrading components puts them in a totally different league. Guess you won't know for sure until you do it.