Thank you, yes I sent my logo to somecompany to digitized, and when I tried to do my logo on a polo it was like you said a bulletproof, it was very thick, it look ugly.As was mentioned above, underlay is merely to stabilize the fabric and provide a foundation for the top stitches. This is where the push/pull compensation is taken care of for the fabric type, and also to help with densities. Proper digitizing also prevents the push pull effect by changing stitch angles/ lengths, and by not sewing a design from one side to the other. Most, but not all, of the companies that charge by the stitch count for digitizing, could care less about putting more underlay to minimize top stitch count. They have no incentive to do so. For me, a density of 4(the industry standard) is about as heavy as I ever go. With proper underlay, 4.5 will cover pretty well and not make the design seem bulletproof(meaning heavy and thick like a bulletproof vest). No two digitizers do things the same though, and you have to learn what is best for you.