I bought a Raymarine ST40 Wind instrument that failed when lightning stuck the boat 3 slips down from mine. I'm not blaming Ray for that though. While it was working, I liked the display, but could not get it calibrated well. I tried the procedure several times, and it always showed the apparent wind incorrectly on port tack. Oddly enough it seemed to be accurate on starboard tack. I don't know if I am going to replace this instrument or not. The wind speed is helpful, but I was always getting headed on port tack if I relied on the display.
It is hard to beat the old reliable windex, although my ears are pretty good when I balance the wind on each side I know I'm facing right into the wind. My bimini is at the canvas shop right now getting a window installed above the helm. I may not know how fast it is blowing, but I will darn sure know where its coming from!