Well, WOW, Ging! Took me all night to read it--I couldn't stop!
How great was it that this all started with Harry and Draco being themselves, fighting over Snape's body and ALAKAZAAM! Poor Snape. First, your narrative description was so well done; the reader was transported to this world with them, and could so easily sense and see everything along with the characters. When Harry and Draco sicked up from the chlorofom, my stomach actually gave a few sympathetic lurches.
I really enjoyed the breaking down of that wall between Snape and Harry, all chronicled by that noble and skilled observed, Watson. It was clear that Snape and Holmes respected each other, and that seemed as it should be; two great intellects such as theirs would jump the wizarding/Muggle barrier, I think. There were so many intricacies to you plot, so many times when I had to sit back and admire your genius: Encantadora, the mended wand, the fourth Hallow's story, the house of inverts, Holmes in disguise, working in Stonehenge. I could go on and on. Draco and Harry's gradual but hesitant friendship made perfect sense; nothing like a common enemy to make them reexamine each other. And Snape himself was so IC and verbally devastating, while Holmes and Watson seemed to step right out of Doyle's pages.
I love both of these worlds so much, so I can't tell you how satisfying it was to read such a well-done crossover, where the reader was never overwhelmed by explanatory exposition, but immediately drawn into another fascinating adventure! You did an amazing job of it, Ging, and it was well worth the wait! Single malts all around! *celebrates with you*