I have a Keychron K2 with some retro looking keycaps and blue switches. I don’t know for sure how it compares to the K7 though.
It’s a really great keyboard, solidly built, not too heavy, nice sounding and even nicer to type on. The battery holds up pretty well, I rarely have to charge it.
I don’t carry it around but it is pretty portable.
The only thing I‘m missing from my original MacBooks keyboard is the little globe button on the bottom left for emojis, special characters and such. But this is mapped to another key combination so all is well. And it is pretty high, you might need a wrist rest for very long typing sessions. In my usecase (gaming and a few hours of uni a day) I don’t struggle with this.
It is connected via bluetooth with up to three devices at a time and you can swap between them via a keyboard shortcut. It has a switch for MacOS/iOS and Windows/Android so swapping between devices is almost seamless.
There is no software for it afaik. For me thats a plus (less bloatware on my devices), but if you want highly customized lighting or super elaborate custom behavior, it might be a minus.
Overall this is a great little keyboard, especially considering that I got mine on sale for 50 or 60€.
Germany too