This right there is the difference between a vendor who sells stuff and an engineer who makes stuff. 0.5 bar
across the primary cats!. No wonder these things are so happy when they're uncorked!
The weight thing doesn't surprise me. The only way BMW with all their resources was able to improve on the stock exhaust was to use super-thin Inconel, pretty much ignore aesthetics except for some sorta nice Ti tips, and charge $3700+ and they were only able to drop 20lbs. Add the additional complexity of the valve system (Which I personally can do without but I understand the draw, I have a dump on my pickup truck) and you're there.