I use the walking foot that came with my Brother all the time with a generic quilting guide (and use the same foot on my Baby Lock and Kenmore but it won't fit the Pfaff). If you do buy a walking foot, check to see if it has a hole on the back to accept the guide. Yes, because of those feed dogs on the walking foot, you can't use it for anything but straight stitching. Maybe gentle curves, but I've never tried.

Some machines have a walking foot that has a guide that attaches to the foot. My elna has this, that's why I know that you can have your cake and eat it too.LOL.

Yes, zoo the walking foot is for straight lines. Without it, especially with your quilt sandwich, the bottom feeds slightly more than the top. With it, it feeds both top and bottom at the same time.

I absolutely love my walking foot! When I was new here to the list that was one of the first recommendations made to me by TWMBO (those who must be obeyed- kind of like the wizard of Oz of the group- they are out there, but we can't always see them). It made my quilts SOOO much BETTER!

I use it for those straight seams and putting on the binding. Great investment- makes the finished product so much nicer and your mood will be too!

My Walking Foot is almost always on my machine! The quilting guide will help yur back! Mark only the first line and follow that line with your guide and boogie!
The WF is a God-send when sewing on curved binding! Saves so much time ( I hate to "un sew").