I too vote stain. Just had our place re-stained (solid latex stain)after 15 years. I'd use a high quality or you may regret it. Latex stain will flake, but it doesn't peel like paint. Oil stain is different, you won't get either. However, I had oil on mine at one time, and I did get algae from where the sun doesn't hit on the siding (north side). Someone explained to me of why it happens with oil stain. If I wasn't so lazy, I could look it up! :) I'm not real crazy about the idea of power washing any wood. Real easy to force water into the fibers and destroy the wood. I don't believe paint will keep carpenter bees away. A relative has painted cedar, and there are bees galore. I spray my place down every year with an insecticide, but you have to be careful around flowers, don't want to kill those bees. I have no problem with carpenter bees.

Even two coats, if he used semi transparent, shouldnt look like paint. Are you 100 percent sure, he didnt use solid color stain?? A power washer wont help you.

We tried doing another coat on one, but maybe just doing those spots is a better idea. The thin we didn’t sand at all, we wants to see what happened. Definitely some of the spots that aren’t on a knot might be from sanding

Being located in Canada, I've never heard of the oil brands you've used previously, although the 6 month time frame description of your products performance sounds just about right for exterior semi trans oil. I've used the Sherwin Williams version of this product extensively over the years. My last house had a hottub deck that needed constant snow shovelling & would consume 10 gallons of semi trans oil every fall for maintenance. I would only ever use semi trans oil for properly prepared clients exterior lumber decks, and nothing else due to product limitations. In the world of ski resort homes I've been using Sikkens Cetol 1 for over two decades on multiple wood species with great results ( *Side note, never top with Cetol 2/3 or any other clear coat) I have large timbers on my own home, that on average I recoat with one coat of Cetol 1 every 3-5 years, depending on exposure. Sure the product costs are higher than a semi trans oil, but then so are the benefits.... A couple points to keep in mind; smooth cedar siding installed horizontally instead of vertically will unfortunately be more prone to marking/future water stains & trapping dirt etc. mainly due to that flat exposed edge profile. Smooth wood will always discolor/dry out/mark faster than the equivalent siding in a rough/er finish & require higher upkeep. Another factor to consider is the cedar sidings substrate. Over the years I've definitely noticed product life discrepancies/variations depending on the sidings backing and perhaps more critically, how it was installed. Air movement is your friend.... Either way, good luck whichever road you take with this !