Stick with strings because they work without batteries or calibration. Lasers fail in bright light or on uneven ground where you need them most. Nothing beats physical lines for trust and speed in real conditions.
Honestly, I've had the opposite happen. Last week my laser was useless on overcast concrete, the line just vanished. Had to dig out a chalk line. For me, the battery and calibration are a non-issue, it's the surface that decides.
Remember watching a crew try to string a fence in high winds last spring... the line was snapping and dancing all over the place. They finally borrowed my old laser just to get a straight shot started. Sometimes the old ways just fight you for no good reason. Makes you wonder what else we do just because it's always been done that way...