[рони]

Velidan,

var tableItems = [].slice.call(this.table.querySelectorAll('td:first-child')),
      cloneItems = [].slice.call(this.cloneTable.querySelectorAll('td:nth-child(3)'));

  function compare(arr, arr2) {
      if (arr.length !== arr2.length) {
          return false;
      }
      for (var i = 0; i < arr.length; i++) {
          arr[i].style.height = arr2[i].style.height = Math.max(arr[i].offsetHeight, arr2[i].offsetHeight) + 'px';
      }

  }

  compare(tableItems, cloneItems);