I would recommend that you buy a few different brands and types and see what your machine likes. I use the same thread for piecing and for quilting - right now a 50 wt 3ply cotton from Connecting Threads. It is a bit linty but I still like it. For piecing I stock up on neutrals and then I have assorted colors for quilting.

My favorite variegated thread is Star thread from Coats and Clark.

When I bought my quilting machine, I got a smoking deal of free polyester thread in assorted colors. Plan to use it up when the color fits.

Regardless of what I buy, I always get it on sale. Guterman, Madeira, Superior.....I'd say start with a basic assortment and work from there. Thread can be a siren call just like fabric and soon you'll drown in spools. lol