I'm not really confident in either defense, but I'm far less confident in Tech on both sides of the ball. There's nothing they could do better about it, they played the teams that they did. It's just not clear at all how they'll look against competition.
Oregon's offense is the most tested unit, but has faded against good competition. I think Tech is a top defense, but has shown vulnerabilities - ASU obviously, but also KSU (Avery Johnson), and pass defense was rough early on. They are also the least tested unit in the entire playoff, so seeing vulnerabilities against their slate is not great.
When Tech has the ball, we will be watching two pretty consistent but untested units. The Oregon defense has not shown vulnerabilities even against moderately better, but not great, competition. The Tech offense has taken care of business all year, but is basically as untested as their defense is. So whichever unit rises to the occasion.
Model says Tech -5.5, but all the numbers surrounding that figure scream low confidence.