I had the same thought process way back when. I bought my car specifically to do the manual swap. I then heard of 517. I did my homework and my manual swap was half the cost of what it costs for a rebuilt 517 gearbox. With the same tune, my car picked up 40-50whp on the same dyno. Think about that. The reality is: even if you have a 517 trans, SOMEDAY, it will need to be rebuilt. My 01E would NEVER need to be rebuilt...maybe a clutch, but that's pennies compared to a new gearbox. Manual transmission is a very subjective thing. If you like a stick car, once you drive a manual RS6, you'll be hooked. To be fair my manual RS6 wasn't my DD, and never intended to be. That may be a factor for you.