Asrock was previously owned by AsusTEK Inc. some years back they detached from the parent company forming their own firm, so we do expect quality products from them.
I also have a planned upgrade to a 990fx mobo after i have sufficient funds but here in India Asus has better RMA service than Asrock as I already had my m5a978 m le bios degraded to a lower version twice due to stability issues.