So what is all this stuff and what are all these terms and what do they mean?
A voltage regulator can change incoming voltage to an acceptable level. It is not a surge protector.
An EMS can tell where the voltage is coming from and distribute it to the correct place - ours is supposed to know if we get power from shore or generator etc.
A surge protector can protect against surges in voltage that exceed safe levels. This could even mean lightning bolts.
A UPS is an uninterruptible power supply that is mostly used to protect computers from crashing if there is a sudden loss of power - with today's laptops containing their own batteries some people do not see the need for a UPS. But there is another factor - some UPSs have AVR or Automatic Voltage Regulation which is like a voltage regulator (ISB Sola Basic) but generally not for high demand devices - mostly only computers and electronics such a TVs - they are more precise than the larger size voltage regulators - we once even had one for our refrigerator to protect sensitive circuits.
There are other devices and some of these manufacturers will have a few different things that may be of use to RV owners. Learning about some of this stuff could be useful no matter where your travels take you.
http://trci.net/products/surge-guard-rv . . . . SURGE GUARD and other stuff
http://www.progressiveindustries.net/our-products . . . . SURGE GUARD and EMS
http://www.isbmex.com/productos/corrector-de-voltaje-8-y-4-kva . . . . . . . ISB Sola Basic - keep in mind - this is important - this is the only one I have found that can both raise and/or lower voltage as needed at levels where higher power needs are desired - can run things like air conditioners and microwaves (though maybe not at the same time). This was covered previously in this thread. By the way - we see both residences and businesses in Mexico with these devices mounted on their buildings. Plenty of people in Mexico have lost valuable devices to varying voltages. They can be ordered from almost any good hardware store in Mexico - though few stock them - should only take a couple days at most as they have distributors all over Mexico.
http://thewirecutter.com/reviews/best-uninterruptible-power-supply-ups/ . . . . opinions vary and there are other brands in the market place.
Even those with no knowledge of electricity at all should have basic circuit checking devices such as the Prime Products I brought up previously in this thread. Even battery chargers can get fried if connected to the wrong circuit (learned this one - bad experience).