Sure they reflect light but that doesn't mean they reflect the proper spectrum. Mirrors are not good at reflecting light back to your plants. The way they are designed, the reflective coating is behind the glass. The light has to pass through the layers of glass two times before it gets reflected back to your plants... Each time passing you lose about 10-20% of your light. So with most mirrors you'd be lucky to get about 60-75% reflectivity.Just a question please dont take this wrong but are you speaking from experience or what you have done? I use mirrors and to be honest never had a hot spot and my grows have been bigger when i switched over to mirrors.
*doob
And yes mirrors reflect light thats just crazy to say it dosent serious think about that question guys