Singapore Airlines KrisFlyer - singapore economy seat upgrade

Hi there
Im about to fly singapore airlines long haul auckland to singapore. They have an option to pay for a better seat on their economy class its 50 us each way. I wonder if anyone that has flown with them before could advise me if it's worth paying for?
Thanks
Josh

The preferred seats are at exit doors. It only means you have extra leg room and won't have other passengers climbing over you when going to the bathroom. It is however next to the bulkhead where there may be parents with babies.

I have done preferred seating before on the A380 upper deck which isn't close to a bulkhead. It was worth it on a very long flight. I've done the Auckland flights more times than I can count but have never bothered with it but may consider it on the older 777-200ER that does SQ281.

I am unable to select any seat due to technical issue. :(