Hey mat,

will depend of a lot of facts, how far are you in the tournament,
how loose is your opponent opening etc.

I would not reshove against UTG open with 2 for example 20 BB but I would against CO especially if he is opening very loose.

I would consider also which tournament is it, like if you are deep running and not use to this stakes, I may won't play the same strategy than if it is my normal stakes tournaments, but this depends on me really :)