Sometimes it isn't who you ask but how you ask.
Sometimes the same people have a lot more problems than others.
Here is an old thread on French drains. I don't think French drains need gravel in our sandy soil, but I am often wrong. That would make them easier and cheaper to install and still effective. Hire a LOCAL person rather than a national one. They know our soil and our conditions..
Warrenty Dept will not help.....
And remember; You can catch more flies with vinegar than you can with honey. People are human.