Aurifil Thread, from Milan Italy, started out as cotton machine embroidery thread, but quilters quickly discovered that Aurifil Mako Cotton Thread was ideal for piecing and quilting.
Aurifil Longarm Polyester 50wt Variegated Thread is the new MUST HAVE variegated polyester thread. It is a 40wt high sheen premium trilobal polyester thread, ideal for embroidery, quilting, thread painting and decorative stitching
this was all I could find on differences- the maco was originally an embroidery thread- but quilters have found it to be a wonderful piecing/quilting thread- in cotton. the machine quilting thread tends to be polyester. *long arm quilters use a lot of polyester threads...cotton breaks too easy with the high speed machines* both are great threads. my machines all love aurafil threads- cotton and polyester- I use which ever I have the right color of- for piecing, quilting and hand stitching