This is the Ethan Shirt from Sis Boom Patterns. I got it as part of the Sew Fab Pattern Bundle and sewed it up to be a part of my son's Christmas outfit this year.
I really was impressed with this pattern. It has all the elements of good construction that you'd find in a regular commercial pattern, but with the clear directions and full-colored, easy to follow pictures you find in PDF patterns. That said, I wouldn't choose this as your first project. I am by no means an expert, but I have been sewing for awhile, and this was a tricky project for me. It was especially tricky because I used a fabric without a right or wrong side, so I had to pay really close attention to what I was doing to make sure that I didn't sew something on backwards and end up with two left sleeves or something.
Another thing I really like is that this pattern does alterations for you. There are different sleeve lengths and shirt lengths, so you can choose the size and then choose the length, making for a perfect fit with no hassle. Be warned, thought, that it makes for a LOT of pattern pieces. Each size is by itself (not nested with other sizes), so you don't have to print them all at once, but I think there is a total of over 100 pages of pattern pieces.