Good question - (maybe slickwraps will respond) - In my experience with any of these skins, it really depends on the case. The tolerances are often so tight that it's tricky if not impossible to get many cases on with a skin applied as well. Others have enough room that's it not much of an issue. The simple rubber TPU cases are often the best for this. I had a simple, flexible one-piece rubber case from Spigen for my 6S+ that had tons of room. Loved that combo. Drop protection plus scratch protection. But that was a rarity. 9 out of 10 cases I've tried with a skin were far too tight.
Do you work for slickwraps?? Because I spent $80 and it took 4 weeks for me to receive a dingy dirty wrap that was way to big for my brand new MacBook Pro. For two weeks I’ve sent photos and order number with no response. I’ve filled out their online form and nothing. I called the 800 number on their website and guess what it’s been disconnected. I’m starting to think they just plant people to leave good reviews and on their fb page they deleted my review the second it was posted. What a scam!