We live just up the road from the medical center at 500 S. Anaheim Hills Rd where you'll find the Drs mentioned here (Johnson, Iseri, Gladstein/Kotoures). We've seen them all, and it's mostly been insurance issues that have caused us to change. We see Dr Iseri now because his office takes CalOptima.
While we respect Drs Gladstein and Kotoures, our son was misdiagnosed back in 2002/2003 when we brought up issues with our oldest (born 1999, now 10). We suspected an autistic trend, and he was later diagnosed with Asperger's Syndrome. Dr Kotoures rebuffed our concerns and ignored the symptoms, leaving us very frustrated and not knowing where to turn for answers. It was early in the process, and our son's behavioral issues were only just getting started... enough at the time, though, to warrant further investigation.
Dr. Anette Johnson, our next Ped., saw the concerns right away and steered us in the direction to a formal diagnosis and subsequent therapies. We would still be seeing here if our own insurance/employment situation would allow it. She also helped with our second son, now 5, who was born with a congenital defect (missing an ear, called "microtia"). We definitely recommend Dr Johnson for your young ones.
We have Dr Iseri now, but have only seen a Dr there once, so it's early to tell how things will go.