Linksys AC1900 Wireless AC 2x2 Router

Any idea what hardware version these are?

http://wiki.openwrt.org/toh/linksys/wrt1900ac

Seeing in one of the photos that it has a fan, it must be a version 1.

I did a basic search for this router at dd-wrt.com and it didn’t show up. After reading some of the issues, think I rather pay the money and get a refurb’d ASUS RT-66u or r. Being I already have one, no issues that I’ve seen.