The 'other style' SSAC KO's fit just like the SSAC's - perfect. As long as you use the right clamps on the crossover with a bit of sealant, there are no sealing issues at all.
Personally, I'd buy the set I have again from DNA. Everyone here seems to think they screwed you all on purpose. Typically, if a person/company screws you, they don't offer an exchange or refund for a different product. They would offer to replace what you have with another of the same, crappy thing. With them offering to pay return shipping, I would say the whole thing was an honest mistake. It is entirely possible they were trying to provide you with what they though was a better product for the same price as the set you actually ordered.
I'm not defending DNA entirely, but just wanted to provide some food for thought.