I am all for DIY if...if it works well and does not look DIY. That's me.
As you may have guessed, I am not a fan of this DIY attempt at sideskirts. Nothing personal.
My thought though is sometimes the apple does not fall far from the tree. What I am talking about is pictured below. Those are early ZX3 sideskirts. They have similar grain finish to the front air dam and look like they belong and not some strip of plastic. A trip to a junkyard or two and a set can be yours. $50 sounds about right. Being used and old, you may want to hit them with some black bumper spray paint. Also, the owner of this Focus completed the black lower treatment with finishing the rear bumper's lower half black. Not sure if that is paint or the infamous plasti dip.
Food for thought: