Newegg via eBay offers the refurbished Asus Dual-Band 802.11ac Wireless AC1200 Gigabit Router, model no. RT-AC56R, for $44.99 with free shipping. That's $5 below our mention from last October and the lowest total price we've seen. (It's also $19 under the best deal we could find for a new unit today.) It features wireless data rates of up to 300+867Mb/s, AiRadar signal strength optimization, four Gigabit LAN ports, Gigabit WAN port, and USB 3.0.
A 90-day warranty applies, although it's unclear who backs it.