I have Sonicap Gen 1, Sonicap Platinum, and Mundorf Silver/Oil in my Cornet2. I never did a stock build so can't comment on the difference, but no complaints on the sound. I can only compare the Cornet2 to a Bottlehead Seduction with Auricaps, which isn't a comparison at all, the Seduction is completely outclassed. The Cornet2 also cost more than twice as much in parts than I spent on the Bottlehead.
The Bottlehead Seduction is a big step up from the phono inputs in the receivers I have owned, and the phono section in an Adcom preamp, but the Cornet2 is at a higher level of refinement.
You are welcome to stop by for a listen if you are in the Tucson area.