Well, the fold boosters do indicate that it's got more tech than the 25.
However, you do have a point that we've yet to see them face off against each other.
In relation to this, based on the fact that it can be outfitted with multiple kinds of armor packs, the 25 seems to be more of a general purpose VF.
So either they're designs built for different missions, or it's a 2 designs representing 2 different philosophies of 2 competing design teams. Cramming every bit of technology you can into the plane versus a simple, but modular airframe that can be customized for different missions based on the packs you attach.