Best thing to do is give all these methods a try on some scrap lexan, or maybe an old lid. See what works best for you, what you are most comfortable with, then stick with that method and perfect it. I have modified my trimming methods over the years to where it is just second nature for me know. I am comfortable with my method and get great results from it, just as Lessen is with his. The end result is what matters, I hate seeing a body that looks like it was trimmed with a steak knife or chainsaw. No matter how good the paint looks if the trim looks bad it will make the lid look like crap.
One thing though, no matter what method you choose, is to never leave a straight cut angle, always, and I mean always round the inside corners, or the body will tear in a right angle cut corner. You can see this in the pics of all the cuts Lessen just posted, all rounded corners.