Waitforseconds vs Time

Ok so my first question.

Since Im developing for mobile I want to optimize as much as posible.

I got two different ways of implementing a solution and wanted to know what is better.

The problem is this, I have Function 1, Function 2 .... Function n, each function its called each "n" seconds.

I wanted to know which solution is best A (with yield WaitForSeconds) or B (using Time)

Code A

 private var waitFunction01 = false;
 private var waitFunction02 = false;
 
 function Update () 
 {
     if(!waitFunction01)
         Function01();
         
     if(!waitFunction02)
         Function02();
 }
 
 function Function01()
 {
     waitFunction01 = true;
     
     Debug.Log("Function01 is running");
     
     //other code
     
     yield WaitForSeconds(3.0);
     
     waitFunction01 = false;
 }
 
 function Function02()
 {
     waitFunction02 = true;
     
     Debug.Log("Function02 is running");
     
     //other code
     
     yield WaitForSeconds(2.0);
     
     waitFunction02 = false;
 }

Code B

 private var startFunction01 = 0.0;
 private var startFunction02 = 0.0;
 
 function Update () 
 {
     if(Time.time - startFunction01 > 3.0)
         Function01();
         
     if(Time.time - startFunction02 > 2.0)
         Function02();
 }
 
 function Function01()
 {
     Debug.Log("Function01 is running");
     
     //other code
     
     startFunction01 = Time.time;
 
 }
 
 function Function02()
 {
     Debug.Log("Function02 is running");
     
     //other code
     
     startFunction02 = Time.time;
     
 }

I find Code A to be "cleaner" and more precise, but I really want to hear what you guys think.

Thanks, Gustavo