I also bypassed the Sonicap Gen I caps in the crossovers with Sonicap Platinum (teflon) caps. After a bit of burn in, I liked them so much that I got some more Platinums to use as bypasses for the output caps in my tube amps. After burning them in for a bit, I liked them so much that I replaced the Sonicap Gen II caps in the input stage of my tube amps with Platinum caps. My system has never sounded better.
To top it off, when I attached the side panels to my speakers, the bass got a lot better (of course!), but more surprisingly, the lower mids also started sounding much better and more prominent. So much so, that I removed 30% of the reticulated foam from my tweeter waveguide, so I could get the sound balanced again. But, that wasn't quite enough. I removed another 20% and that finally gave me a good tonal balance again. The net result was still a very nice, smooth tonal balance, but much greater clarity and transparency over all.