Pretty simplistic, which isn't a bad thing. I like the gradients. However, they look pretty rough, like the image were originally 800x600, stretched to it's current size.
The second one actually just has that weird effect normally, it wasnt resized at all, and in the case of the first one, my pixels per inch was set lower than it should be because I only recently got PS on my new computer, so my settings haven't all been set to their usual, which is why it is somewhat pixelated. I didnt notice it when working on it though because I was zoomed out a bit. Edit: I did a blur on the second one and got rid of the effect that makes it look resized, though theres nothing I can do about the first one.
I'm not sure if it's just my computer or the images, but in the second two (more the second than the third) I can see the gradient lines which doesn't look very good.