Will mat with 8x12 window look bad on 11x14 frame?

Hi everyone,

I have no experience on using mat. I am going to order some mat for my 11x14 frame. As my landscape photos are usually 4x6 ratio, I am trying to crop less. So I am thinking of mat with 8x12 window.

Do you think if the border of the mat will be too narrow? Look bad?

Thanks,

Yang