What's your favourite cheap LEDE/OpenWrt device?

I upgraded from a WDR3600 to an archer C5 V1.2 (hw is the same as the C7) which has wifi problems with openwrt. Ath9k on Archer C7 v2: disassociated due to inactivity

The 5ghz range is much better than the WDR3600 but the 2.4ghz range is worse. The C5/C7 has 3x5ghz external antennas and only small internal 2.4ghz antennas.

The WDR3600 has 2 x 5ghz+2.4ghz external antennas i.e. antennas tuned to both frequencies

The C5/C7 used goes for around the same price as the new MT76 routers like the xiaomi 3g/4a but those are not 100% stable on wifi