So what differences did you hear on the cartridge swap? Did you have to use the step up transformers in your VK P10?
Upgrading from a P10 to a P10SE is a big deal, I did it a few years ago and then to the superpak, another good step up.
Also, are you using the XLR inputs or the rca inputs on your phono stage?
I bet it's a great sounding set up !