Rui CarmoApple supported 802.11n on its AirPort range of wireless devices since Feb 2006, and updated them to support simultaneous dual 5GHz/2.4GHz operation on Mar 2009, with a subsequent later upgrade to 802.11ac before they left that market in 2018.
As of early 2025, I still have five of these in active service, and they have proven to be very reliable and easy to manage, although there are fewer and fewer eBay listings for them.
The earlier AirPort access points were also enhanced to support USB printing and bridging (which is to say relaying), becoming a full-featured repeater.