Couple of other differences: the 200E's had two different receivers, one of which was silver nitride with scroll. You won't find that one on a 280. You will also find 280's, at least in 20ga, with both barrels choked IC. I've never seen a 200E choked that way, although it was made in skeet configuration (manual safety, both barrels choked skeet).

And in both cases, the E suffix is superfluous. Stands for ejectors, and all 200's and 280's were ejector guns.