Best Practice for CSS Clear or Overflow

Having a discussion with a co-worker on what is best practice with CSS clear / overflow. Please shut one of us up and explain why one is better than the other.

JOEL'S CODE (using overflow):

<style>
  .container { overflow: hidden; }
  .one, .two { float: left; width: 50px; height: 50px; background-color: red; }
</style>

<div class="container">
   <div class="one"></div>
   <div class="two"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
</div>

CHRIS' CODE (using clear):

<style>
  .clear { clear: both; }
  .one, .two { float: left; width: 50px; height: 50px; background-color: red; }
</style>

<div class="container">
   <div class="one"></div>
   <div class="two"></div>
   <div class="clear"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
   <div class="clear"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
   <div class="clear"></div>
</div>
<div class="container">
   <div class="one"></div>
   <div class="two"></div>
   <div class="clear"></div>
</div>

Both make this image:

Who is right? :)