I've been a buyer of domains at auction for some time now and I never really focused on "Relevant" content. Just sites with a good backlink profile for PBN's. I'm willing to swap sites with similar backlink profiles in my niche for sites that are in your niche. If you have technical sites dedicated to "DNS, WHOIS, TCP/IP, and anything to do with EMAIL" I'll be willing to swap with you, or perhaps just buy it off your hands. Send me a PM. If you're not able to leave me a PM due to post count, just reply here PM Me.