If you want succulent mind blowing ribs then Sous-Vide is the only way to cook these ribs. I have made ribs before (English cut style) and they came out pretty dang good. See the link for more details...HERE.
What time and temp is always the question. Chefsteps prepared short ribs 8 different ways with times and temps so you can compare. In the past I've used 131 for 48 hours and 149 for 48 hours. Choosing what temperature and how long to cook the Short-Ribs will correspond to how you want to finish them. Well if you know anything about Sous-vide cooking you know it's necessary to brown them after the cook. There's no maillard reaction with SV cooking. So depending on how you will finish the ribs (finish = maillard reaction) the Temp and time will be important. What exactly do I mean? Well, if you plan on finishing the ribs on your BBQ and want to impart a lot of smoke and monster bark you would want to cook the ribs differently than; let's say you planned on finishing them in frying pan, oven or salamander.
Note: some people toss in Sodium Nitrite; Cure # 1 for both taste and to create a smoke ring. If you plan on finishing these ribs on a BBQ with charcoal don't worry about the Cure # 1 unless you want that particular flavor. The Charcoal will give you the smoke ring too. If you plan on finishing them in your oven or on a propane smoker and you want the smoke ring a little cure will help in that department too. A smoke ring does nothing for flavor. Cure # 1 will change the flavor profile of course. If I was to add Cure # 1 I would use .25% at a percentage of the weight meat.
What did I do? I knew because of the Rain/Wind storm here in Seattle I would need to use my propane smoker. I always prefer charcoal though. The smoke ring is not important to me but I kinda of like the texture and flavor profile of a little cure. The Ribs weighed in at 3630 grams * .25% = 9 grams. I used 9 grams of Cure # 1. How to apply? I combined without measuring my Rub and Brown sugar and removed a cup. To the cup I added the 9 grams of cure and mixed thoroughly. I then sprinkled this on the ribs making sure to coat the entire rib. After the initial coating I sprinkled on more Rub/Brown sugar mixture. Don't forget I Dry-Brined these for about 55 hours.
Vacuumed sealed for the dry-brine and water bath. I have chosen 144 degrees for 48 hours. This temp should be perfect for the following reasons. As I recall 149 degrees was fall off the bone great but I don't want fall off the bone. I want a little bite and chew for these ribs. Besides I plan on smoking them until an internal temp of 160˚ƒ. If you look at some of the Chef Steps Videos you will see why I chose 144 at 48.