If you can find a low mileage, one owner, well maintained vehicle and manage to negotiate an extended warranty, as I did, buy it. Last Dec, I found a 2004 V10 loaded that was traded back to the original dealer with only 25696 miles. I negotiated a platinum extended warranty (not a third party, but VW warranty) for an additional 72K miles/6 years. I love driving it, I love the acceleration. The only thing that puts a similar smile on my face is my ZX14 Kawasaki (with regard to acceleration that is).
It wont be without some risk and you will see that parts (without the benefit of a warranty) can be expensive. I have had a few tiny issues. New software for the center diff to remove the clunking, new comfort convenience module (keyless entry/locking), rear seat belt hangup in lowered position (real PITA) but no show stoppers.
If you need an excuse to justify something you are already going to do, then do it. But listen to the voices of reason here. Without the safety net of a VW warranty, I wouldn't have bought mine