Implementation is a b!tch.
Hypex modules themselves test very well. Just refer to any of the ASR reviews of the NC400 DIY, or any of the work done by Buckeye.
Dylan's builds are quite pure in their use of the Hypex modules. I believe some of his newer builds will be going for review soon, but preliminary testing for his new input board is proving clean.
Anybody interested in 6- or 8- channels of NC252MP or NC502MP would do well to check out his offerings!