Decals Are For Bumpers
You stumble upon a rotting '59 Chevy in an overgrown field. While the metal rusts away, still visible is the "Vote Kennedy" bumper sticker.
If vinyl is good enough for a bumper, it should work well on a t-shirt, right?
Vinyl is for decals. Ink is for t-shirts.
With a DTG printed or sublimated t-shirt, the design will in most cases outlast the garment itself, much like the bumper sticker on the '59 Chevy. In 5 years, that t-shirt you can't throw away because it is "just broken in" may have a hole in the arm pit, but the print will still read "OBAMA 2008" instead of " BAM 2008."
The popularity of performance and athletic tees are raved about as being lightweight and moisture wicking. It's like wearing nothing at all, another layer of skin. But then someone goes and sticks a vinyl decal on it. It's like nails against the chalkboard. You don't stick a decal on your skin, you get a tattoo!
Unless you're a decorating a '59 Chevy, say no to decals and say yes to Wally's no-feel, no-fade, no-peel custom designed prints on your favorite garment.