Brice, I appreciate your remarks, but I have three concerns:
(1) you can't get delivery confirmation with FLATS. For some it is not important, but I like it.
10.2.2 Eligible Matter

[1-22-12] Delivery Confirmation is available for First-Class Mail parcels and First-Class Package Service parcels (electronic option only); all Priority Mail pieces; Standard Mail parcels (electronic option only); Package Services, Parcel Select, and Parcel Select Regional Ground parcels (electronic option only) under 401.1.0. For the purposes of using Delivery Confirmation with a Package Services or Parcel Select parcel, the parcel must meet these additional requirements:

(2) I often mail old poker chips and club chips and old inlaid chips which are not as strong as current casino chips, so I sandwich them between bubble wrap and cardboard and put them in a heavy kraft envelope. So I might have a "uniform thickness" issue with FLATS.

Uniform Thickness -- Flat-size mailpieces must be uniformly thick so that any bumps, protrusions, or other irregularities do not cause more than 1/4-inch variance in thickness. When determining variance in thickness, exclude the outside edges of a mailpiece (1 inch from each edge) when the contents do not extend into those edges. Also, exclude the selvage of any polywrap covering (see 301.1.5) from this determination. Mailers must secure nonpaper contents to prevent shifting of more than 2 inches within the mailpiece if shifting would cause the piece to be nonuniform in thickness or would result in the contents bursting out of the mailpiece (see 601.2.3).

(3) I also like to throw my mail pieces in the collection box, not hand them to clerks, so I have no one to argue with if an issue is raised.

Robt.