We have a really challenging stain situation. Five years ago, we had a general contractor apply Sikkens (now part of PPG) Log & Siding stain on our split log siding. This is a semi-transparent oil stain. The problem is, the wood wasn't cleaned and prepped properly after they power washed the old stain off, so the end result of the stain is that it's way darker than it should be, and there is wood fuzz/felting everywhere from the aggressive power washing. It's looked pretty bad for five years. Since Sikkens is a five-year stain, we decided that this year, we'd clean the wood and re-apply the stain properly, doing one side of the house at a time. The problem is, Sikkens is a VERY hard to remove stain. In an effort to try to clean the old stain off, I ordered a gallon of this Defy stain stripper (Defy's parent company is SaverSystems). I followed the directions, let the stripper dwell on the wood (wet) for 20-25 minutes, and then power washed it off. While I could tell the Defy was doing something (running your fingers over the siding after application, you could see the Sikkens stain color coming off on your fingers), after the wood dried, it didn't look like any stain had been removed at all - the color looked the same! After one application of Defy and no results, I emailed Defy's customer service (parent company: SaverSystems), explained the problem I was having, and asked some questions. The lady I spoke to, Tricia, wrote me back the same day and answered my questions. She said that yes, you could apply multiple applications of their stain stripper without damaging the wood. She was very apologetic and even offered to send me an extra gallon of stain stripper to help me finish the job. I said, "cool, send it on!" Note that I also emailed Sikkens and asked them how the heck I'm supposed to remove their stain. They never responded. A week later, I received not just one gallon of free Defy stain stripper, but 10 gallons! And a couple of gallons of their wood brightener! I was amazed at the extra mile this company went to try to help me with this impossible project. In the end, on the one side of the house I worked on, I actually wound up having to hand sand (random orbit sander) off the Sikkens stain. No stain stripper would remove the Sikkens (I tried a different brand's, as well). But if you have normal, non-hardcore Sikkens stain to remove, I would highly recommend Defy's stain stripper because 1) it does seem to dissolve oil-based stain, just not ours, and 2) their customer service is out of this world amazing. read more