Unexpected Underdrive pulley benefits?

[Asianoak]

Okay, I've searched and haven't found anything yet so figured I'd ask the experts.

I recently installed a MS underdrive pulley along with an AFE intake and I've notice a considerable difference in how the car drives. There are the usual things likes bit more responsiveness. But my question is whether or not anyone else has experienced other benefits. I've noticed the transmission shifts much much smoother than before, it actually feels like it rev. matches when I downshift. It did not feel like this before the install.

It's so different I wonder if the car has a tune installed that would take some of these mods into consideration. Noticed SS brake lines had been installed by the previous owner... perhaps there are other mods as well?