Last I heard there is 4G only in Mexico City - and that is not real 4G - even 4G in the US is rarely really 4G.
Many factors affect speed and connectivity. We have been in areas where Telcel is decent one minute and non-existent the next minute.
As far as WiFi - that too can vary from minute to minute. The biggest factor being how many people are using that particular WiFi source and what they are using it for. One person streaming video on WiFi can ruin it for everyone else trying to use that WiFi. If no one else is at that RV park the WiFi can be very different than when 10 or 20 or more users are active.
We use WiFi whenever we can if it provides us with what we need. We use Telcel when we have to or when the WiFi is to slow to be usable. Sometimes Telcel is too slow to be usable. Since we have to pay for Telcel by the GB we try to limit use by using any available WiFi.
We use an ALFA WiFi distance booster (www.rokland.com) which allows us to use WiFi in our RV even when quite a distance from the WiFi source - while others have to walk to the office carrying their laptop we sit in our RV with a good signal - about $30.
We were in an RV park a few years ago and they were on what was then Hughes Net as I recall. They were on satellite. There was some limiting factor and if too many people tried to do too much then the whole system went down and there was no internet for a day or so. They told us Hughes knew how much they used per day so if people tried to stream or something like that then Hughes punished them by cutting them off. I am not sure if that is fact but I do know the internet did go down and could be non-existent for a couple of days.
Things are getting better as far as internet and phone in many areas of Mexico but there are still areas that get no service. There are still many areas of the US that get no service or where service is slow. We can be in areas with our Verizon in the US that shows we have a 4G signal but we still get poor speed.
