I have not seen the mice go after the plastic loom? There are pros and cons to the plastic / braided loom. If your running the wires in the fender well and not under the hood the plastic loom is better. If you are running the wires under the hood, I agree, The braided is better looking. The plastic is easier to remove-re install if needed. The braided will raise the price as its more labor intensive to install. We are debating what to do there......
For starters it takes a week and a half to read thier "book" that is the instruction sheet! We can call that 1/3 of the time savings LOL. You have to loom the painless harness, That alone is a massive time waster..... You have to : Figure out what to do with the big lump of additional circut wires that you do not need, Re layout the direction the wires go under the dash, figure out how your installing a dash speaker after you install that big fuse box, the sad firewall grommets you have to fight with. on and on.... I am not saying its not a decent product. I am just saying ours is an easier install.
I have installed them all. Our harness really is the fastest and easiest to install.