Difficult to pick one "greatest". I have have been pleased with all purchases I have made here and have made a friend or two along the way. If I had to choose one purchase, it would be the Wadia 850. It was the most expensive audio purchase that I have made, ever. I had buyer's remorse from the get-go. I will give it up when they pry it from my cold, dead hands.
What's your greatest purchase...
from this site? Mine was the Ars Filarmonia which will hopefully arrive this week.