Chosing right fermentor

I am about to get me a ss brewtech conical fermentor, but dont really know if i should get the 14 or 17 gallon.
I want 10 gallon into my keggs.

How much loss is there when draining the yeast out off the cone ?
How far down doeas the racking arm go ?

Dont want to buy the 17 gallon if i dont need it.

 

I have the 17 and have yet to determine losses because I have yet to fill it accurately. I have made 2 13 gallon batches with it. I am sure if I get near the 17 gallons i will end up with 15 gallons of finished beer. If 17 will get me 15, 14 will certainly get you 10 gallons of beer.

If you are absolutely sure you never going to want more than 10 gallons get the 14 but for $100 more the half barrel would give you more beer.