I LOVE the bunker wall! Eliminates the possibility of a skulled shot coming back at you too...
Andy Staples used a lot of rock walls on his project in Hobbs, NM (both as cross hazards and to define boundaries (photo looking back toward the 5th tee during grow-in). I hear he's using them a lot on his remodel of Meadowbrook CC (near Detroit) too so maybe he's turning into a "rock wall guy".