That's longer than they need so they'll dry out some over that longer cooking time. What device are you using? Do you have network access or the abiltiy to set a timer for it? My anova can be started remotely via the app with the Anova on my home wifi and on.
If you can start it remotely, set up your cooker with enough water to reach the intake, then the bagged steaks, Ice to the top. If you can set it up in a small ice chest, all the better as the insulation will keep it ice until you're ready. Then just add about an hour to melt the ice and come to temp, then another 90 minutes would be my preference for that temp and thickness. It will vary some by container size, how much ice you're using and so on. Worth experimenting with one weekend so you know how your setup works in this situation.
The proteins continue to constrict forcing out more liquid and the muscle fibers become more pronounced, forming the "strings". It's not fast and it's not like they'll be bad or unpleasantly dry, but they could be better. Where steak is so tender anyway, it doesn't need a long cook to have a good texture.
8 Hours is probably too long for a cut like that. Some cuts would hold up and need that amount of time, or even longer (36-72 hours) but a ribeye runs the risk of getting mushy and mealy. I wouldn't recommend it.
I'd say you are probably fine for about 4 hours...but after that you run the risk of mushiness. The ice batch/remote start is a good idea...probably your best bet.
Is there a reason you can't just start it 1-2 hours before serving?
EDIT: There might be another option...the good ol' cook/chill. This is the method most restaurants use for most meat proteins, and it works fantastically. Are you able to cook the meat the night before, chill, and store in the fridge? Then you'd just have to bring your water bath to about 125F the next day and drop your meat in for 20-30 mins before serving. Then sear as normal.
I've been thinking about a sous vide since I ate a filet mignon that was prepared by a caterer using a sous vide. so I've been researching sous vide. Serious Eats' J. Kenji Lopez-Alt wrote an article on steak sous vide. Timing is one of the factors covered in his article. He tested steaks at 1 hour; 4 hours; 24 hours.
Done as you propose, the steaks will have great flavor and a slightly mealy flavor. With a tender cut, you want to hold it at target core temperature as briefly as possible. Myself, I've found sous vide disappointing for steak, though you can transform a really tough cut into good steak this way. But cuts already good as steak, like rib eye, are best cooked just to core and seared.
I ended up taking the tenderness of the rib eye cut most into consideration and decided to just do a reverse sear. In the oven at 300 to about 110 tempered then a super hot pan. Quick brandy cream sauce and the family was fed. I'm intrigued though to try it on some tougher cuts as you say.
I would only use Sous Vide for steaks if I was trying to cook a 2" Ribeye, NY or Filet. If your frying up a 1" steak it's easy enough to just cook as you normally would. I think of Sous Vide for beef as longer cooking slower process. This is a bottom round that was Sous Vide and had for dinner yesterday. It was in the water bath for over 40 hrs. After cooking at 130 degrees it was rare and tender. We pasture raise and corn finish our cows. I have hundreds of lbs of roasts that don't have a fat cap that I would want on the roast if I was roasting it. This method helps me cook and tenderize the meat while not over cooking the outside layer.