I think the "first" comment is based on that they made it specifically to function with BH209. BH209 was the main reason for the design from day one. T/C Omega type plugs are very good but they were not designed around BH209. They just happened to work well from the start. The Lehigh/Knight plug was designed around BH209 and we tested it very well when only Lehigh offered them. Ive even burned 2 boxes of WinT7 primers just to prove how well it works with BH209. I wonder how well the T/C plug would work with the same primer? It should work fine but ive never seen any reports.
The original test bed for BH209 was actually the Savage breach plug. Technically they were the first but still require more maintenance than the Lehigh.
BTW i would expect another first to be coming if the rumors are true...and its pretty damn nice from the talks ive had. AND NO DO NOT PM me for what it is.