If you have a self draining cockpit with decent drains, feed it to the cockpit.
The pipe runs are shorter, and as you said, its for emergency use.
I feed 2 rule 3700's and a 240v mother of all pond pumps

to 3 outlets low on the aft bulkhead directly into the cockpit..
Hope to gawd I never need them lol...

I do have a deep cockpit, but installed 2 new 3 inch drain tubes directly through the transom.. to add to the exisitng somewhat undersized bath plug hole type drains.
With the direct to cockpit, you dont need valves or loops or highrises.. you can even use plastic waste pipe and fittings with a small flexi piece to the pump.
A good tip if you go this route is to fit a small flap valve over each outlet - looks neater and stops any backflow if ya get pooped !

Joe