I'm not sure what the situation would be for the V6 TDI. I know that the V10 is somewhat rare, so it can be harder to find an independent mechanic for some "engine related" jobs.
In general, I've found that some routine services will be cheaper with an independent mechanic, but some will not. Remember to figure labor and cost of parts/supplies for any given job. Most of my dealership service was done at Aristocrat in Sanford, but I had my most recent oil change done at Maus on Lee Rd. I prefer Aristocrat for service.
Though I have never used them, I have heard good things about Full Throttle in Orlando. Be aware that they are scheduled pretty far in advance (probably a good sign).
PM me if you would like to discuss further.