If I read it correct, when voltage drops to 90 - you'll get 109, and when it shoots to 150 - you'll get 134. Doesn't look too comfortable.
Is there anything with 30A input that keeps output 110V+-4% withing say, 90-155V input range, and shuts down when it can't keep it? Not just a "mejor voltaje", but "correcto voltage"?
First - the standard is 120 - not 110
Second - I have always said you still need a surge protector of some sort - a couple of units mentioned in this thread. The surge protector will keep you safe.
Third - What the ISB Sola Basic Voltage Regulator does is keep the incoming power at a more stable level than some places might provide - this is not true everywhere as some places do have stable voltage.
The mentioned surge protectors will cut off power to your vehicle if the incoming power goes below a certain level (I have heard between 102 to 108 depending on where the info comes from) or above a certain level - usually 132. With the ISB your voltage remains in the safe range and the surge guard does not keep cutting your power. BUT the surge guard is still there to cut power if the ISB cannot keep you in the safe range.
With our ISB in most places we have been our surge guard almost never cuts our power. That is the whole point we are trying to make here. I hope this helps. There is a lot or reading and useful info in this thread but you have to read it all to get the point. We keep rehashing the same info over and over.