doest take as much space as regular thread, I get about 2x's the ammt with bobbin thread

A spool of bobbin thread came with my embroidery machine. Accidently used that bobbin in my sewing machine and it did great. Now I buy a spool of white and a spool of black bobbin thread and use it all the time for all sewing. It is thinner and you don't have to wind bobbins all the time. The only time I match colors now is for the free standing lace patterns and for topstitching clothing where it might be seen.

There seems to be two different things being discussed here. For clarity:

When piecing, i.e. sewing fabrics together to make a quilt top, it doesn't matter if your threads match. I agree with a previous poster about finer threads, such as Bottom Line, giving you a more accurate seam, especially with miniatures. I started using BL for this purpose and fell in love with it, so now I use it for all of my piecing. And as Lynnie said, because it's a finer thread, you can get a lot more on the bobbin which means fewer reloads.

When quilting, i.e. sewing top, batting, and backing together into a quilt, most quilters I know prefer to use the same thread so that imperfections in tension don't show.

Hope this helps

I use thin thread for my bobbins when piecing, the thinner the better. I have started using pre filled bobbins and they seem to last twice or triple the ones I fill. When machine quilting I use bobbin thread that matches the backing. I've never given much thought to matching the bobbin thread to the top thread.

one advantage about having the same thread in both when quilting is that if your tension is a little off it's less noticable than if you have a different color thread in the bottom. I personally use whatever neutral is available when I'm piecing and pick color/thread for appearance when I qullt - so I'm frequently using different threads top and bottom.

You can also use invisible thread in the top rather than embroidery or quilting thread. We've used it for hemming dresses using a blind hem when we had no match for the color. You can also baste with washaway thread. The top washes out, and the bobbin thread just lies there ready to remove.

Bingo.... This is what I was looking for. Thank you very much !