Great install, but the glass center shelves are something that makes me say DUH!
Many times I wanted built in lighting, but unless over every shelf the lower units are in the shadows. Glass is the answer but then you have light duty glass shelves and lose the woodiness look of the unit.
Solution here, a simple wood frame (duh!)
Good tip about the advantages of springs, they rarely lose their gas and as you say, easy to adjust!