Congrats Tom it is an excellent piece of kit - I have one to use with the 150mm F2.8 gives me a 210mm prime at F4. 
No noticeable loss of image quality and auto focus is fine. 

And every one said, 'If we only live,
We too will go to sea in a Sieve,---
To the hills of the Chankly Bore!'
Far and few, far and few, Are the lands where the Jumblies live;
Their heads are green, and their hands are blue, And they went to sea in a Sieve.

Edward Lear
http://www.nonsenselit.org/Lear/ns/jumblies.html