Running a standard carb fuel pump you shouldnt need to fit a regulator. Most carbs(bike or other) need ~3psi so you can measure your current fuel pressure if you want.
Me and stephen set up his bike carbs with a wide band just driving around the streets and a set of jet drills. You set up the idle fueling with the needle height.
In my escort the economy cant be complained about, its not bad at all.
There is probably more to be learned about the little ports at the inlets of the carbs but they dont seem to have a big effect on normal running, the ports would normally be inside the airbox but all setups I have seen have them looking at atmosphere.
One thing which is different with bike carbs is the linkage is smaller than a car carb which means a shorter pedal movement in the car unless modified.
There isnt a problem with either setups but for me, I would go for bike carbs as they are cheaper and newer, new sidedraughts cost a bomb and old ones are all pretty worn from what I have seen