I guess the correct answer depends upon the requirement.

I like this way

  <root>
   <item key="name">John</item>
   <item key="city">London</item>
  </root>

So I can use this xpath to get the person's name:

  //root/item[@key="name"]/text()

Not sure what would be the xpath to get the name if the XML was

  <root>
   <item>
    <key>Name</key>
    <value>John</value>
   </item>
   <item>
    <key>City</key>
    <value>London</value>
   </item>
  </root>

This is a better example:

  <employees>
   <employee id="1">
     <field name="name">John</field>
     <field name="city">London</field>
   </employee>
   <employee id="2">
     <field name="name">Jack</field>
     <field name="city">Boston</field>
   </employee>
  <employees>