Oh I forgot to tell my (literally) painful experience, the moment when I realized the lie about converting the DRM protected files to non-DRM files.
To use these converters you have to launch the Spotify app on the same computer. I had it logged in to my Premium and also previously, by mistake, the output option was set to my AV-receiver via Spotify Connect. And when Sidify or the likes started to "convert" the song, it started to play on my receiver in hiperfast rewind velocity on - probably - zero db which means f*cking loud. It was scary, but fortunately not at night. I think I was able to turn off the amplifier quickly, before it damaging my speakers.
But hell, be cautious!

 

Registered today just to post an advertisement for NoteBurner in four threads? Not very convincing.

 

I've tried several such Spotify Music converters before...Sidify, DumpMedia, TuneSolo...oh yes their trial version(I didn't pay before I decided to subscribe to anyone) TBH, DumpMedia Spotify Converter might be the one that works the best among them.