Recovery Formulas are Great for a Post Workout Shake. They are composed of a 4:1 Simple Carb to Protein Ratio. Recovery Formulas are made up of, usually, sugars and Complex and simple carbs. This is likely due to the glycogen depletion that your body encounters after vigorous exercise. I personally use a Recovery Formula and Not a Protein Shake mainly due to the fact that I have seen better results with the Recovery Formula than a Protein Shake.
A Recovery Drink contains:Simple and complex carbohydrates for excellent glycogen replenishment*
A high Protein Efficiency Ratio blend to provide the critical building blocks for rapid muscle resynthesis*
Vitamins, including antioxidants, to help reduce muscle soreness after an intense workout and assist in repair and growth*
Studies show that with proper nutrition during the first hour following a workout you can increase your body's ability to recover more than 100%. The key component to maximizing this "window of opportunity" is a formula of approximately 4 parts carbohydrates to 1 part protein. With Taking a Recovery Formula after my workouts i have little to no muscle soreness and my body is rejuvenated after 45 minutes.
If you are trying to gain muscle mass and develop lean muscle and don't mind a little weight gain due to you putting on muscle because of the addition of extra protein in your diet, then I would Suggest using Whey Protein And Casein together for maximum benefits. BUT if you just want to reduce muscle soreness and help your body recover to about 100% then i would suggest going with the Recovery Formula. Recovery Formulas contain more carbs for more sustainable energy and also have some protein in it to assist in muscle repairs