N.M.
We also use Mid-Cities Pest Control, and the last time one of their reps came, he said he was using an organic solution rather than the chemical one because it was so much safer. That was about a month ago, and so far, we've only seen a couple of bugs. You could call and ask specifically for him - I don't know his name, but I think he was British or Australian.
We've been using MCPC for 5 years and we've never had a problem with getting them to come out for a "touch up" for free between seasonal visits if we find bugs. I'm completely arachnophobic, so we have to have regular pest control visits, and I've always been pleased with their service and professionalism.