I've been taking my kids to Dr. Sandra Arca in Grapevine for 6 1/2 years. She has also has a female office partner, Dr. Harston, and 2-3 NPs. My kids don't get sick often, so sometimes I only go in 2-3 times a year (for well child visits and maybe 1 or 2 sick visits), but they're great about getting you in at the last minute and answering questions over the phone. As a matter of fact, I briefly switched to a different ped when my second son was born (closer to our home), but switched back to Dr. Arca after about 6 months because the new doctor couldn't get us in the day my child was sick, which has never been a problem with Dr. Arca.
I have a few friends who go there as well, and one doesn't like one member of the office staff - the only male, but I don't know his name - but other than that, I haven't heard any complaints about the staff.