Well I was a 100-400 guy so I didn't do a ton of special endurance 2, but when I did it would be something like 2-3 x 300 with full recovery. Lots of my teamates that didn't do the 100 seemed to bennefit from the same workout with 450s.
Special endurance 1 would be something like 3 x 250 with full rest.
The differences between speed endurance, special endurance 1 and special endurance 2 are explained very well here
I would say any good 400 program would have a nice mix of all three.