has used metal filters for years. I guess maybe they have changed that now with their new bikes. The stainless work well. I started using them in my KTM as I had to buy two filters. I change oil alot. It was pretty pricy. So I went stainless. I have well over a year on my 520 E/XC now with them and have had zero problems. I've heard of other Yamaha
owners re-using the stock metal filters for a year or more. Just clean, inspect and, re-use. It all depends on how long you plan to keep your bike and how offen you change oil. The SS filters will pay for themselves over time. Some folks don't like the idea of having to clean them. To me its no big deal. Takes just a minute or so. I use a hair dryer that I keep in my garage to dry them off after cleaning. For me it beats the heck out of having to buy paper filters in bulk. Just my .02 cents.