When we first bought our Eagle I really didn't like the power awning (as we always had a manual one).
However, after camping with it going on 5 years now, I find that it's actually just fine.
We leave it open during the rain, in fact it's never rained so hard that it's caused me to retract it yet. It doesn't have a dump feature (at least if it does it's never done it) but it also has a pitch to it so it drains fine.
I like the push button aspect, although I didn't mind having to deal with the manual one in regards to putting it out and retracting it.
Honestly, my favorite thing about the power awning is not having to deal with the arms angling down to the bottom of the trailer and walking around them.
Having said all that, if I had my choice it would still be for the manual awning. Never had an issue with the power one, actually like it...but still prefer the manual one.