Need to purchase a KUL - HKG ticket, am a One World Sapphire member. Can I select seats without a fee when booking discount Y tickets due to my Sapphire status?

What are the loads like on the KUL - HKG fights? I certainly don't want to be stuck in the middle seat and will pay extra for a prereserved seat if I can't preselect a seat with no fee as a Sapphire member.

Thanks.