I went through this same contemplation. Ride quality was a slight factor as was money.
The initial "cost" isn't that different if you go with the EVO ENF with the king 2.5s. With the king 2.5s, you can go pretty fast and still have a comfortable and stable ride off-road. "On road" is pretty great with the Enforcer out of the box.
With the coilovers, you'll be able to go faster off-road because of the dual coils and timing ring controls. You can also adjust ride height. But here is the rub. With all that extra speed comfort, you'll push the limits of other stock components. So now you are looking at axle shafts or full axle replacements.
I went with the Enforcer and King 2.5s. Added front king air bumps to help a bit with ride at higher speeds. For the most part I'm able to the hang with the coilover folks. I've put tons of miles off-road and onroad. miles in just over a year.
No regrets with my decision though others can certainly justify their own decisions. Everyone has different considerations. Can't really go wrong.