I'm getting a frame built for me that I plan to build up myself. The drivetrain will be a ten speed Campy Chorus/Centaur mix. I can save a more than $80 if I use better bang for the buck Ultegra hubs and an American Classic conversion cassette rather than Centaur or Chorus parts. With 105, the savings get huge. So, has anyone done this? Is the shifting with the AC conversion cassette comparable to Centaur or Chorus cassettes? Am I destined to misery and frustration as the price of saving a few bucks? I do understand that Campy permalink chains won't work with the conversion cassette, but I plan on using a Wipperman anyway.