A correctly designed rig with high performance fit will reduce any restriction points to a minimum. Other areas concerning Performance and the success of the modern rig lies in the perfect balance of form, function, durability and price. Probably the most subjective of all and the one that most people base their choice on, is the cosmetic factor. People have come to believe that rigs are like automobiles, just select the style and color you like. They all will drive down the road.
Price is another area of subjective determination.
The value of the product is determined by whether or not the individual feels that they are getting their moneys worth. Like buying an automobile, if you want pay the lowest price for your car, then there are many econo-boxes around that give excellent value for money. However, performance is generally lacking. The final area of performance is whether or not the manufacturer delivered what they said they would. Remember, we're all human and can make mistakes.