Yeah, I get that frustration—nothing worse than killing something that might've turned around with a bit more data. For me personally, the very first thing I check is usually the early conversion rate combined with how the EPC is trending after like 5-10k impressions. If the clicks are coming cheap but nothing sticks on the backend, that's often a quick kill signal unless the landing's getting tweaked. But honestly, what actually determines whether popunder traffic converts better than native or banner in 2026 funnels? A lot of times it's the raw volume and predictability—pops can give you that massive scale with decent enough targeting and frequency caps, while natives feel warmer but slower to ramp. Banners just die off fast for me in most verticals these days. I tend to give pops a longer leash if the initial ROI isn't tanking hard, since they often surprise you once optimized. I tried to use this https://www.allydigitalllc.com/ Just my two cents from running a bunch of these lately.