I have had both, and a couple of Biostars, and an ASUS Vintage PH-1 and I've built at least 3 shuttles and I would say that if you are looking to spend good money on something you want to last, buy the Sugo. They are both quite cramped inside though and if you use a full-size PSU then the optical drive length becomes critical.
Shuttles and the like come up quite regularly on Member's Market. Post sensibly, but often, get youself in there and see if you can't get a proper bargain.
And I still say that the ASUS you were looking at is a perfectly adequate piece of kit.