I find it much faster to do FMQ than any straight lines. I have a sitdown Sweet 16, and I use a ruler to do the straight lines since the S16 doesn't have feed dogs. Ruler work is much slower than anything else, but it is sometimes the right thing to do for the quilt. I am currently working on a baby quilt that is simple large blocks. The plain blocks have FMQ and the featured fabric blocks are getting scalloped ruler work -very slow but very appropriate to the fabric.
Pam