I'm going to comment based on context after re-reading your original post a few times...I was not familiar with the term "whip hose". If I am interpreting things correctly, you intend to use a remote container for the finish with your gun and the hose you are mentioning is for fluid flow. If that is correct, I'd rather have a little more than a little less as it lets you keep the pot out of your immediate work space. I used to own the remote 2 cup version of the Wagner HPLV conversion gun that was identical to the regular gun I was using at the time. (I recently sold it to another 'Creeker) The 10' hoses that came with it were functional for common projects but not really long enough to do "big work" comfortably, so I bought longer ones to use in those situations. So honestly, your decision comes down to what puts the finish container in a comfortable, out of the way place for you during your work? Personally, I wouldn't go less than 6', but you need to keep things reasonable relative to the turbine hose, too.