I agree with buying small amounts of different threads to try out. Preferences vary by machine and quilter!
Having said that, I recommend trying Glide thread from
http://www.bobbincentral.com/quiltin...ead/glide.html . This is a thread that tends to work on any machine, and that many quilters like. It never breaks or shreds on me, and it imparts a subtle sheen that adds a little sparkle to my quilts. You can call or email the company in order to buy just one spool to try out (to bypass the minimum order requirement). This is my "go to" thread. I have dabbled with others but for most projects do not like them as much as Glide. I also love their matching magnetic pre-wound bobbins, although I also wind my own bobbins. Mine is a frame setup, but this thread works equally well with sit-downs.