Has anyone used the Pypes universal 3.5" X pipe system?

I am looking to build a 3.5" system for my Barracuda. I came accross this Pype's system and it seems like a decent value. I would be using it on a 68 Barracuda with TTI headers that have 3.5" collectors.

Why 3.5"? It currently has a 3" system that goes to 2.5" tailpipes after the Ultraflow mufflers. It has exhaust cutouts and picks up a tenth and a mph with the cutouts open. I would like to build a good enough exhaust system to not need cutouts. It has been 10.60 through the full system.
Link to Pypes System


Thanks for any information.