Too often at LHR T4, I find out -- the hard way -- that the Terraces near Gate 1 is much less busy (and significantly quieter) than the First or Terraces lounge near Gate 10. That said, it's no fun to hike back and forth, especially if your gate is at the other side of the terminal from the lounges.
On a Terraces to Terraces basis, I like the arrangements for Terraces near Gate 1 better.