I held back on this one but here goes. I have no experience with the Lexjet material and it sounds interesting.
In a previous life, I supplied Decalgirl.com with all their vinyl and laminate. In my experience, only cast vinyl printed on a solvent or eco-solvent printer, laminated with a thin cast laminate will do the job you are hoping to do. Think of it as a small vehicle wrap. I did extensive research with Decalgirl to achieve their goal, which was a skin that can be applied and - here's the key - removed up to three years later without leaving any adhesive AND without removing the paint that is on most devices. Decalgirl has prototypes of almost any device that comes out and test all before making templates for printing. BTW, Decalgirl is a privately held company run by the best husband/wife team I have ever run across. I can't say exactly which brand of material Decalgirl is using (NDA and all that...) but cast material is the key to success. In addition, most printed vinyl images will rub off pretty quickly if lamination is not added to the image. Especially on a cell, iPod or any device that is held in hand as a function of use. Unless you have a solvent printer, I'd just buy a skin. Beware: many skin vendors don't laminate their product or guarantee the image permanence.