The acid test for me on new signings is;
1) Would they be good enough to secure or seriously compete for regular starts at Adelaide, Melbourne or the Roar (these are the teams we will have to compete with to be title contenders).
2) If not would they make the squad at those clubs and
3) Are they better than the player they are replacing in the Nix squad.
If the answer to 1 and/or 2 is yes then the answer to 3 will almost always be yes but not necessarily so (think Smeltz & Moss).
The answers, for me, with resepct to Diego are yes so, as long as we can get / keep him fit, he is a good addition.