Yes on my Nagra VPS. Makes a real difference. I am not on my Nagra MPS or Classic amp. I've heard the VFS under the Jazz at my dealer...(and when I had my PLL I had a 2nd VFS) it's easy to hear the benefits and ditto under the MPS (tried this at my dealer too). My dealer does have the larger VFS for the Classic, I am sure he'll bring it by one day soon :-)
Good luck tomorrow. It takes a bit of break in...will sound good from the start...but get better in a few weeks. I just let my Classic play 24x7 for 2-3 weeks. It relaxes, more ease, more resolution...more weight on the notes.