Aero Turbine Muffler Power loss?

Hi guys, I have installed an Aero Turbine 2525XL muffler on my Tacoma 2010, love the sound and immediately noticed a smoother ride on the road you can say. But I have notice what feels like a little loss of power, has anyone experienced this with an after market muffler?

Example today was driving up a steep hill and it felt like I really needed to stomp down on the gas. I did get my muffler installed at this shop really cheap but now am wondering if maybe they did not weld it on right or something.

 

loss of back pressure can mess with low end power n torque.

 

Could this be a side effect of an aftermarket muffler? Or because of improper install?
Is there anything I can do to correct this like adding a resonator?

I guess am just wondering if I should go back to stock .

 

Maybe if it is installed backwards. Probably just a shitty designed muffler.

There is the answer in my opinion.

 

I have the same muffler and didn't notice any loss in power. Just the opposite. Butt dyno, though.