Worth paying for seat assignments LAX to Dusseldorf?
 

I'm using AA miles and just called Air Berlin to see about seat assignments. They charge for pre-assignment $24 and up. However, if I'm willing to take a chance I can book a seat online 24 hours before the flight. It's two four and two across.

Does anyone know if it's necessary to pay to assure an aisle or window seat?

Have you tried called AA for seat assignment?

I had to call Air Berlin. They explained that I'd have to pay 25 for an aisle and 40 something for a window. Otherwise I might be in the middle. They do release some aisle and window seats 24 hours before the flight without charge, those probably get grabbed fast. At least I think this is the system.

AB is unusual in that one can see the seating plan with seat prices before committing to a booking.
So do a dummy booking and see what is available - they have quite a variety of pricing.
On cash bookings I pay for the emergency exit row.
I'm not sure whether you can do that on redemption, but if so I would say it is worthwhile.

I never pay, and just grab a seat at check-in. Always works out if I check in early.