I bought the LV10 as someone suggested it wasn't too loud, as it was too loud I bought this insert which didn't help much at all. If you like your lv-10 and want it a little quieter get this... But it only helps 10% or less.
Easy installation, definitely makes a noticeable difference. I’d say it reduces the sound levels by 15-20%, which is perfect for me. The LV-10 slip on is loud to begin with. I live in a house but if I lived in an apartment complex I would probably not go for the LV-10 even with this dB killer because I would not want to annoy people leaving for work at 6am.