Corny Keg on a long run sanke system?

Hey all,
I currently keg all my batches into 5 gallon corny kegs and use standard ball lock QDC. The bar I work at has three bars with a keg cooler in the basement. The run to the main bar is 40ft with glycol cooling.
So heres my question...
Can I just change a sanke hook up in the keg room to a corny QDC and use one of my cornies the same as a sanke? We have the back pressure set so that foaming is minimized, is there any reason I cant just keep it at the same PSI setting (as I would for a sanke keg of beer with a similar volume of CO2).
I cant see any reason it wouldn't work, but I would hate to lose a gallon or more in the long lines just to find out it didn't pour.

Thanks for the help,
Ben

is this for after hours? sounds like alot of trouble serving home brew in a bar.

40ft of 3/16" tubing only contains 53 cubic inches (1.8 pints) of volume

Never sold, never served to customers, never poured during business hours. Haven't yet brought any to the bar. Only brewed for the master of the house and guests (I dont care for guests). Thanks for prompting the fine print.

The line must be longer than 40ft then, they hold a little more than a 64oz pitcher (some foam).

It should work, technically. My concern would be more the legal side and the gray areas in the alcohol code. Things as stupid as not getting the beer from a distributor can be huge issues in some areas... It's a great way for the bar to loose their license.

Long haul would be larger that 3/16" tubing...

I'd also be worried about ATF.
However, dump a gallon of ****beer into an empty cornie for the trial run.
Can you just put a plastic party tap on it, and carry it up when needed?

No difference in the pour. There are adapter kits available to make it easy to switch back and forth.