Most sites recommend "1 hour per inch of thickness" for meats. I will double or triple that sometimes, if the cut of meat has a lot of tough sinew, silverskin between muscle groups, or other connective tissues and hard fats that need time to break down - beyond when the meat itself would be considered done enough.
That does not mean I would double or triple the time for roasts and such - you can over cook via Sous Vide - resulting in a mealy, un-natural texture. But, for cheap cuts of steaks and chops which have been known to you in the past as a tough cut of meat...try it! I think the strength of SV is it's ability to make a cheap cut of meat taste and have the texture of very expensive cuts.