Best Smartlinks for Pop-Under Traffic (Mainstream & Adult)

Hey guys

Quick question for anyone running serious pop-under volume.

Who currently has the best-performing Smartlinks for:

• Mainstream / e-commerce traffic
• Adult traffic

I’m mainly looking for strong RPM, worldwide coverage, good GEO/device optimization, and aggressive monetization.

Which networks are performing best for you right now, and who would you say has the most aggressive