There is one thing you should do, as you can see the corners are not rounded. Use magic eraser to erase the area around it and then save it as .PNG and it will make the cornes rounded. I'll show you..
.JPG and didnt use magic eraser.
.PNG and used magic eraser.

But yeah they are very nicely done! I like them alot, i even would like to get one myself. =) If you have time.. =D