The finishes of this small shelf are fairly mediocre. It fulfills its moderately shower shelf role because small bottles and tubes take over evil (the mesh is not stable) and take them down. It's been a month since I asked and it is still not rusty. Stainless steel looks good but I have not enough experience to tell. It seems to take too. The attachment system (kind of paste that sticks to the tiles but can be removed without damaging the support) is effective.
Edit 11/12/13: rust appeared on the shelf after 4 months of use. It is supposed to be stainless steel! What a scam!