Pelikan, you make a good point but the figures do not add up against the experience.
On a headset with poor passive attenuation the active section when turned on will sound more impressive - but is that what you want.
Any active headset is better than passive for long periods in the cockpit and they make radio reception much clearer. You should also consider the number of hours spent in the cockpit. If you are an instructor pushing 4-5 hours per day the outlay is worth it. If you spend 1-2 hours per month are you going to notice.
For me I would buy either the Dc 10-13.4 passives or the Bose and I would not bother with anything in between. Bose are the daddies, make sure the batteries are kept charged and enjoy top quality aviation sounds.