If price is no object (USD 60+++ per bottle) and you want something special (both excellent, rare and recognizable), try one of the Kikuhime premium sakes ("BY", "GIN", Kurogin or Kukurihime, for example). For a fraction of that price try Kameizume (hard to find and great value). There are as many sakes as there is wine (and with a similar range of flavour and quality), so it is really impossible to give you advice blindly, but if you mention those names to the store clerk they will recognize what quality level you are looking for. Personally I prefer Momokawa Pearl (made in the US but otherwise authentic).