I've been buying silicone wiper inserts on eBay that ship from Thailand. They cost me about $6-7 per pair and they come in both 6 mm and 8 mm widths in varying lengths and can be cut to fit. They've been working well for me for over a year, but my car is in a parking garage by day and my garage at night. I have three pairs staged to go on my GF's and my son's car at some point. Those vehicles are parked outside so that'll eventually be the real test. Silicone wipers don't work well for all vehicle/wiper arm/blade frame/windshield angle combinations. Strange, but true. You have to try them. If they work well for you, they WILL last longer than natural rubber.