How do i know

Heidrun,
Look for upcoming audio shows in Northern Europe or wherever you can journey to, and check out the brands that are showing such as Ayre. Dealers are also usually listed. Now you can trust your ears.

I purchased Horning Hybrid speakers from Denmark after hearing them at the RMAF show in Colorado. I went there to listen to another speaker that got great reviews and that I was ready to get, but their sound did not do it for me. I do my very best not to purchase what I do not hear.
Kenny

It's called "paying your dues". It would be wonderful if you knew which equipment would meet all of your needs for the rest of time. Which recordings would suite your taste. Of course we don't know this. We would save so much money. So educate yourself and learn to read between the lines in audio reviews. Take some chances and one day you may have what you want.

If you are buying new, from the same manufacturer, reach out to the manufacturer and perhaps they could point you to another dealer even in another country that would be willing to demo for you and perhaps help make those arrangements for a demonstration. Coming through the manufacturer, you may get treated very well by such a dealer, even if they aren’t the selling agent due to territorial restrictions that may be in place. It’s a plane ticket, and maybe an excuse for a weekend get away. Worth a try.
Otherwise, agreed. It’s hard to assess stuff until you get it in your room, in your system, and live with it for a while. That’s why there’s so much turnover in gear, leaving aside the "gotta have the latest" mentality.