I use the magnifier that attaches to the machine for all my SITD sewing. The ditch looks deep and wide through it so it's easy to stay next to it and not fall in but I sew right in the middle of the seam. I can't machine quilt without the magnifier. It's inexpensive and Walmart has them here. The lights on it aren't worth being on it so I don't even turn them on. I also have a the goose neck magnifier floor hand stitching lamp that is excellent for when I use my regular sewing machine. I put it in front of my needle. It makes a big difference in my piecing. And it uses batteries too if the power goes out. The light is very bright.
http://www.simplicity.com/p-5219-cc-...magnifier.aspx machine attachment
http://www.mightybright.com/Magnifie...-and-Magnifier I bought it at a local needlework shop but it's cheaper online at Amazon and Sears has some really nice ones.