Well it's certainly not a dramatic departure from their original designs like Miku Append was, that's for sure, though I guess my only real problem with that was the feet really.
Personally, I find this design fascinating because it was made by the same artist who did my most favorite Hatsune Miku fan-art. Just look at his most recent art, it's the Miku Append one. I hope that's what got him Crypton's attention to allow him to do the design for Kagamine append.