Straight cut edge with a blade for sure.
I don't cut SA but I took over a bunch of my bermuda lawns from some hack job guy who's idea of "edging" was to scalp the turf down level with the pavement with a string trimmer.
It took about 2 months of no edging to finally get the grass to fill back in where he had scalped it every week.
Some of my neighbors in subdivision do that too and it looks awful. I kinda wanna stop and give them an edging lesson sometimes but I don't wanna come across as an ******* who's in their business. It is their yard afterall and they can what they please. It just aggrivates me looking at the butcher job.