I just did both to my home. We chose espresso prefinished red oak for the main level and then did a sand and stain to match on the existing red oak upstairs. I will say with the darker colored prefinished you can see the lines between planks more prominently as mentioned before, especially where they have been cut or trimmed during installation or if any glue has seaped through (if you're doing a glue down installation). I went back and did some touching up with a stain marker. To have unfinished installed and then stained on site would have been much more expensive, so to me this minor touching up was worth the savings. The on-site staining is a bit messier and required some paint touchup, but overall I am in love with both floors! Good luck!
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Floors
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