Question about TP-Link M8550

No, but we've been travelling in the Czech Republic and the motorhome for two weeks now and have always had excellent reception. Of course, this could simply be due to the network coverage. We are very happy with the device. The only thing is that it generates too much heat, it overheated once a day when in constant use.

Netgear 6000451-10000S

TS-9 connector

Yes, I have already used it with two external antennas (5G). With a TS9 to SMA adapter, you can connect commercially available antennas. I have two magnetic short antennas, which provide the necessary reception in weak reception situations.
The device can be switched from internal to external reception in the menu (directly on the device).
I am satisfied with the product so far. Especially the permanent use without a battery.