I love to use the 40 pin AVR chips and, as they're not included in any kind of Arduino, a dev board is always great to see.
This one has a great AVCC power supply which is ideal if you want/need good clean ADC reads.
But it would have been better if the headers were at a 0.1 inch compatible pitch so that I could mount this board on a larger stripboard or matrixboard layout. As it stands I have to sacrifice 0.1 inch compatibility to get the advantage of this board's power supply, or use a different compatible board but have to sacrifice the nice AVCC supply.
This board also doesn't have a built-in blinky-LED, which the other board I use does.... but I'm still yet to decide if that's actually an advantage or a disadvantage. ;)
All-in-all a great board that would be perfect if J3 and J5 were positioned just a little to the left.