Next question. Can you trust it? Really trust? If not then using it as a decision to RTO is an interesting one. In the normal takeoff brief about reasons to RTO it mentions a/c unfit to fly. Are you linking this scenario under that heading? Remember most takeoffs are at reduced power; all takeoffs assume loss of 1 engine. So, an increase in tailwind, or loss of headwind should be coped with by an increase in thrust on ALL engines. It would really be a very bad hair day to have a sudden shift in wind AND an engine failure.
I remember at Mombasa B757. Naturally a warm day and a gentle breeze from somewhere. Off we went at reduced thrust. I thought I saw the far end of the runway getting closer than expected and we were still <V1. Push up to full power and we rolled through the mirage and lifted off in half the runway. A pilot colleague in the cabin, during our long missed en-route cockpit visit/chat, asked about the sudden power bump during the roll. I explained and he understood, fully.
Like many have said, IAS readout plus looking at the far end might give more an accurate picture than a tiny wind arrow display. What does AB say about using it and its authority to make RTO decisions? Is it a nice toy put there without any particular guidance how to use it. The same is true for FPV on B737, but that's another story. If anyone wants to go down that route please one a new topic.