I have the Genelec 8030C speakers, and also a SAM set - 8330A speakers, 7350A sub, and GLM Kit. The speakers are set up side by side on identical stands, while I decide which I prefer to keep. I stream to the digital inputs of the SAM gear from a Fiio SR11 streamer with Neutrik impedance converter. With the sub bypassed, I prefer the 8330A speakers by a small margin. Adding the sub makes quite a difference. My room/listening seat results in notches in the 8330A frequency response, and the sub crossed over at 100 Hz effectively deals with the lower frequency notches. I'm not a bass freak, but I do enjoy the firmed-up bottom end that the sub adds, too. I could probably add a sub to the 8030C speakers, and improve SQ with them, too, but the GLM Kit is a very user-friendly solution, and allows on-going functionality that external solutions would not.
My system is strictly for music enjoyment in my home. Listening seat is about 9 feet from the speakers. I actually have two 7350A subs at the moment, which is not needed in my room (24 x 16 x 8 feet). In a much larger room, or for very loud playback the second sub might make a difference.
I do enjoy the 8030C pair, too. Initially had a Denafrips Pontus DAC, then switched to a Cayin RU7 DAC which I really enjoy, too, with a Schiit Freya+ preamp in passive/buffer mode.
It's only been a week with the side-by-side comparison, so I'll give it some time, but I'm probably keeping the SAM monitors and sub.