I live in the UK we do not get many US products, presumably due to the ridiculous taxes. Do you know that for an item to come from the US to the UK, the importer/customer will pay US sales tax, shipping costs, UK taxes on the gross (including tax on tax and tax on the shipping costs), incur ridiculous delays at UK customs as well as pay extra charges to the courier companies for "customs clearance charges". The UK customs treat everything from the US as if it has come from some sort of terrorist country whereas you can import anything from the far east no probs.
Therefore, everything in the UK is made in China. It is a challenge to get something non Chinese in the UK.
So I ended up buying a "best seller" from Amazon, hoping it will work else I will return it. It is rated 300W, but I only plan to draw less than 70W. Still I wonder if it will work at all.
In addition from my experience and people's comments these inverters make lots of noise as soon as you try to pull any power, and you must add devices incrementally else they trip during startup and refuse to start.
So I was thinking how hard will it be to make my own. Take an old 300VA troidal transformer, make a 12V p2p square wave generator or sine wave if needed, plug it to the transformer backwards and job done. The square wave would have good efficiency.