Seimien is a decent to good backup in this league but that's only because there aren't a lot of good backups. Tyrod is a much better starter.
He's 25, and has played pretty well so far for a 7th round draft pick. Needs to learn to step up in the pocket more, and step into his throws. He keeps fading back and floating passes and he'll be a backup before long. I don't see top end starter in his future, but i see him as a journeyman plug in starter.