Matías & Tamara: they look like they'll bicker a lot (not Jonathan/Victoria-like, but more like Lake & Michelle), though they are really competitive
Casilda & Casilda: they are the powerful underdogs, they know their strengths and how to complement each other.
Ricardo & Adriana: they seem like a light version of Ronald & Christina
Daniel & Carlos and Gabriel & Guillermo: Fit but absent-minded, the mental tasks might prove hard for them
Ariel & Nora: absent-minded, not that fit, they'll have to rely on their luck if they want to survive
I didn't see enough of the other teams to form a solid impression.