Like I said, it's your call, but I see illumination as an unnecessary novelty in most cases. But the difference in weight is less than four ounces in the three you listed. If you can tell a four ounce difference in a fully loaded slug gun with scope mounted, you're a better man than I.

Edit: Duh, forgot to answer the question. I don't think it will make a difference with that mount, you should be fine. The amount of difference weight is going to make on that type of mount is below the margin of error for most shooters.