It depends on what you are going to do with your PC. Gamer? 2500k. Movie producer? 2600k. Regardless of which CPU you nab, that G-Byte UD3H is the board I recommend out of the three you linked.
I have had good luck with Gigabyte boards. Unless someone changes my mind between now and Sunday, this is the one I'm going with.
Now to decide between 2500k and 2600k!