I went to see my ortho today, and I am in my final months of braces!! October 1st I'm getting impressions for a retainer! Yay!

I want to ask my ortho if I could be given an Essix retainer instead of a Hawley. My reasoning is, to be quite honest, I know that I wouldn't wear the Hawley as directed. Since I'll just be getting my braces off, I won't want any more metal wires in my mouth for a while. I'd probably just wear it at night and show off my bare teeth during the day if I was stuck with a Hawley.
I did some research on WikiPedia, and apparently, a few orthodontists aren't particularly fond of Essix retainers. Knowing my ortho, I'm going to guess he's one of the few. I have never seen him give out a single Essix, and I think that if I ask for one, he'll shoot me down. He shot me down for Invisalign even though I was a candidate.
What can I do? I don't want to waste all that money and time invested into braces, and then just have my teeth slide back to the way they used to be! Help!!