May

Technically, these images are very, very good. There is no loss of details in the shdows and no blown highlights, even with shots right into the sun. You have combined the three images very nicely; tricky stuff like the water works quite well too.

As a rule, I tend not to like HDR images because they somehow don't look quite right, but that is not overly apparent in this image. I find the separation between the clouds and the sky on the left adds a nice three dimensional look and feel to the image.

Compositionally, I like some of the other images that you posted along with this one a bit better because the foregrounds are more interesting to me, but on the other hand the HDR artifacts are more apparent too.

I shoot with the D90 and Tokina 11-16mm too, but tend to stick with a 0.6 grad filter. I know that the shadow details get lost and there the setting sun showns blown highlights, but prefer the look.

Anyway, congratulations on some really compelling images!