So you rate Higuain higher than Cavani?
Hard to say my man. Both are fantastic, but based on their record and current status Higuain is the 'better one'.
I personally think La Liga is glorified beyond belief and a 20+ goal forward there wouldn't be a 20+ goal forward in Italy, but I can't tell the exact ratio. Anyway Napoli aren't selling Maradona and there is a chance he might flop in another team (or not be that good as some pointed out) and the price has to mitigate that risk somehow.
On the other side Higuain is clearly 2nd choice these days, but Real being Real it just doesn't say anything. Not to mention he has (like Torres) the president behind his back trying to stick something into his anus which isn't exactly the support one would hope for, just because he was brought by another president unlike his competitor for the spot. His form should have dropped a long time ago...
I know there is no reason for Cavani to be more expensive than Gonzalo. That is for sure.