i would rather have my deck lid bolted on. im sure the tape works great too and is very inexpensive
Keep in mind the reason why aftermarket is "cheap" is because it's just a piece of plastic. You can bolt on, and there are a few ways, but that involves more cost. OEM includes both bolts and tape. So you'll need tape anyway.
Also, with tape only. When you just put it on, you can still take it off before it's set. Just incase it does not lined up properly. Believe me, your steady hand all of a sudden becomes shaky.
And without a template, you have to be 100% sure where to make drills. All the moons and stars must lined up. If it's off, you are SOL. And it's permanent.
True, there are downside in using tape only too. Mostly that it will come off over time. I'll assume you'll wash your car a few times a year. That is a good time to check to make sure all is good. If there are signs of weakness, then you can take care of it, way ahead of time, before it falls off somewhere.