If we're not going to look at signing someone like Alexis Sanchez (looks like he wants to stay in Barcelona anyway) or maybe Jackson Martinez then we should not bother with signing a 'good' 26-28 year old striker like Osvaldo. We already did that with Vucinic, Matri, Quagliarella etc.
If we are going to put €18m-€20m down make it on someone with a lot of potential who might not make an instant impact but will in perhaps 6-12 months. I'm thinking of the money Milan paid for El Shaarawy, Roma for Lamela, or Liverpool for Suarez. We need to develop our own world class players with that initial investment, because we are not even in the market for world class strikers.