Shoot. Bummer. No, don't know Waterway, sorry. I like my Pentair. Nothing to compare it to, but it's been trouble free and still looks newish after 9 years. After looking at your pics, I certainly wouldn't want anything other than a stainless steel band holding my filter together (which is what Pentair uses). What's on the Waterway? I couldn't find what their band is made of ("metal" was all I could get from Google). You could try pushing back on the warranty company and whoever they sent out to do the install. Maybe insist on Pentair? These guys don't make much money on these warranty calls, and need to get on and off the job asap to stay even slightly profitable. How hard did he look for the Pentair? How long would it take to get one? I know from experience these guys will swap in cheaper parts if they think they can get away with it. Can you wait? Maybe the Waterway is fine. Hopefully someone here will know...