You don't see them much from a rear look, it looks like 4 lines coming down. It's very hard to take good pics of them as they are small & painted black. That's why it's best to look at them from the side.
This is just to give the underside between the 2 mufflers some details. If you take a look at your gas cover the indentations are already there. I also made them that they don't pass my mufflers, in other words my mufflers will hit bottom first.
Everyone that has seen them in person likes them.
If I can't find a way to make them at a low cost I'll just get them made for my car and call it a day.
All 3 parts are not aggressive but do give alot of detail to the car.
I'm a picky guy and I have to say they look great and don't forget these are temp parts, the real one's will look even better.
My eyelid design which haven't been seen yet will be a little more aggressive than the ones on my car now.