I think Vistaprint uses silk screen transfers. What you really want is a place that works with vinyl transfers! It's pretty easy for them to do a single color (like white) for a logo, and it shouldn't be overly expensive. A buddy of mine has a machine for working with Vinyl, its almost like a CNC machine type deal that cuts the vinyl for you using an image you upload onto a computer. After that, it gets heat pressed onto the shirt. Much better quality than silk screen transfers.