I have purchased Thread Art poly. It sewed OK on my Viking. If you are just going to monogram, I would get Black, white, beige, navy, burgundy and a dark green. If you are going to do machine embroidery designs, it would be good to invest in an entire set of colors so you get the weird browns & beiges that give the designs depth.
Some machines are picky. I would order a spool or two from various manufacturers to see which one(s) your machine likes best.