fuerza de la señal

That depends.   Im almost always at 'good' connection,  and service is really good.  If you're in an area with a lot of people and traffic, you.may be bumped to lower priority

454 is awesome!   I am consistently showing a good gateway signal, with 80 to 120 download speeds depending on the time of day.

I was told an external antenna wouldn’t help, but am curious as well if a cell booster would, and which models might work best..

Folks on here have reported good results by adding external antennas, so I'm not sure where you got your info.  It does require, however, that you open your unit and do some delicate stuff to it.   Folks seem to have reported less favorable results with cell boosters….but this may be because they didn't get the correct units that support TM's 5G N41 and N71 bands (which are expensive and also use external antennas).

Gracias por tus comentarios.   I thought the t mobile tech who told me that was all washed up too.  Every other source, and common sense, tell me an external antenna would help..  I hooked one up to my sagemcomm gateway but I think it was too close to the gateway to really help, so I couldn't refute. He had me set set up two networks, one 2.4g only, which seems to help signal consistency, but causes problems when communicating between devices not on the same network.   
 

If anyone has better results with a cell booster, ext antenna, or with the newest gateways (at least one has external ports already) please post it!

I’d recommend using something like Cell Mapper and Google Earth to determine where the tower is that you are connected to first, and if there are ‘any’ items between your modem and the tower (i.e. wrong side of house, tree, building.

Move it to a location which can possibly give you better signal, and possibly rotate it.

Similarly I actually tried it outdoors (or screen door open) and got a much better signal

Cleanest line of site + rotation = going from 2 bar to 4.  and ~250Mbps to ~550Mbps.

Distance will make a difference as well… I’m ~1200’ away, while some are +1 mile, but can physically see the tower.