Transformer Based Inverter VS Transformerless

During the 1990's virtually all U.S. made DC to AC power inverters were of a low frequency, transformer based design. These heavy duty, high surge capacity inverters were built by U.S based companies like Trace Engineering, Vanner, Heart Interface, Outback Power and others. Their inverters provided long life expectancies, (typically 10-15 years), they could start and run virtually any inductive or resistive load, they could be easily repaired and they were very safe to use. One of the few negatives that these inverters possessed was that the use of an iron core copper wound transformer made them relatively heavy and expensive to manufacture.
Chinese manufacturers immediately recognized the market potential for inverters in the U.S. so their engineers set out to design an inverter that replaced the the expensive heavy duty, iron core, copper wound transformer with a complex mix of light duty, far less durable high frequency components. While they succeeded in designing a functional high frequency, transformerless inverter, unfortunately their design not only provided a much poorer surge (peak power) capacity, it also provided a much shorter life expectancy. Even with light duty, intermittent use, these high frequency transformerless inverters could only be expected to last maybe, two to three years.
The reason for this is that these inverters operate at an extreme high switching speed of 2,000 to 15,000 time per second versus the slow 60 times per second switching speeds found in low frequency inverters. And as anyone knows, the more times and the faster that you turn something on and off, (especially cheap Chinese made components, the hotter they will run and the faster they will break.
This fact didn't matter to these Chinese designers. Their logic was that as long as these products could provide a couple of years worth of service then it was all good as far as the the end user was concerned.
Thousands of factories sprouted up all other China building these cheap, short lived, low surge, high frequency inverters. They were loaded into 40 foot containers destined for U.S. ports where they were sold to millions of American consumers through retailers like Harbor Freight, Walmart, The Home Depot, Amazon, Ebay, at truck stops across America, you name it.
Despite the fact that these cheap, poorly engineered. potentially dangerous products had a very high failure rate, had trouble starting many inductive loads, and were even starting fires, unknowing Americans couldn't wait to get their hands on one. Wow, a 3,000 Watt inverter for less than $300! Let me have one!
Even today, after millions of these inverters have either burned up or simply won't turn on anymore, Americans are still snapping them up at their local retailer, ignoring lessons from the past.
What's worse is that today, these Chinese manufacturers are stuffing this same lightweight, light duty, low surge, short lived, high frequency inverter technology into supersized metal and plastic boxes and have hired an army of youtube, affiliate advertisers to push these products with little to no improvement, to a new generation of American consumers.