There has to be a reason why you cannot find reviews. I would recommend against buying a full system from the sub contractor. They are not experts in AV, they build homes. Get the place fully wired for sure but wait and buy a high end audio/video system from a reputable manufacturer. If you want home automation that integrates with your audio/video there may be other options.
Here's a post from someone like you looking for info on Legrand ONQ. I am not familiar with it. I see if offers some kind of home automation but may be seriously lacking in the audio/video dept.
Looking for Input on the Onq / Legrand Unity Home Automation System.. - AVS Forum | Home Theater Discussions And Reviews
What is your focus? Home Automation or Audio/Video or Both?
This page may help
What’s the Best Home Control System?
Google for more. The more research you do now, the better. You may regret hasty decisions.