My CO miles are in my account!
Yes maybe "e-rewards" does have more restrictions, but at least you can (provided you have enough) put 2000 miles into CO, 2000 miles into AA, 2000 miles into US, 2000 miles into NW, etc.... However with "e-miles", you can just earn 2000 miles per year (500 miles * 4 qtrs) for CO alone.
And you can still earn both e-miles and e-rewards!

And free miles are free miles!

(I'll take them both!)