[Gerry Zagorski]

If you are using braid then line capacity is not an issue and I would consider the 4000 since as you said, it's lighter and it also has a higher gear ratio. Both of these things are going to cut down on your fatigue if you are casting and reeling a lot.

5000 has 20 lbs of drag and the 4000 is 15lbs. You're hardly ever going to need that additional 5 pounds of drag unless you are planning to fight a Tarpon.

The 5000 would be my choice if you fish mono since you are not going to get enough line capacity out of the 4000 if you use mono.

Throw all this out the window because you are comparing specs and theory here. What you need to do is visit one of our sponsor shops and see how the reel matches up with the rod in terms of size and balance and comfort. If all things are equal here and you are using braid, I'd lean towards the 4000.