OK, so Bamboo = wood, and it usually has a foil coated foam underlay for insulation - that very effectively blocks WiFi signals... Asus is a good answer. Google HG Gomes firmware, contact him for...

Looks like it's not on their website so not launched in US yet. It's probably coming soon. What WiFi router are you using on the top floor? Does your house by any chance have wooden floors?

With the latest 3.2.4b firmware, the AV2000 is of similar reliability to other TP-Link adaptors I have used and will likely be faster than older ones depending on your electrical system...

Note that the physical link speed on the tpPLC utility is always way higher than the actual line data transfer rate...This is normal for Powerline. The maximum actual transfer rate of those devices...

Powerline adaptors will not let you change region firmware for most updates via the tpPLC link utility. If you really want to do that then it should be possible via the recovery utility posted by me...

See https://www.ebuyer.com/793699-tp-link-tl-wpa9610-kit-av2000-gigabit-powerline-ac-wi-fi-kit-tl-wpa9610kit