These routers are working great, I received the 3rd batch already. 4G is working great (EU), but it's needed to follow instructions and poweroff before inserting SIM card. The only very minor issue when using official OpenWRT is a non-working status LED. All other OpenWRT functions are fully working. Support is quick to answer and resolve issues! This is probably the best OpenWRT device you can buy. The price is good, performance is great (dual-core/4 v-cpu, enough ram and flash), very stable and integrated 3g/4g makes it perfect.
Product as described, fast shipping, no issues setting up. This model shipped with a custom OpenWRT version. It can be flashed to the official OpenWRT version through the recovery procedure. It works with the zbt-we1326 image. I didn't test the 4G function yet. I will plan to order more units if the tests are successful.