Wind trainers have WAY less resistance than fluid trainers, all you have are those tiny little fans and wind resistance.
I had a wind trainer before I got a heart rate monitor, but it never seemed to give a realistic workout, I could spin out
in my top gear, not nearly hitting max effort.

I bought a Kurt Kenetic it matches my real world speed/HR really well. I did a sprint on it when I first got it and was
really pushing it at 34 mph and was still 2 cogs from my smallest in back, so it seems pretty dead on.