Originally Posted by
Candace
A vertical bobbin makes one less "S" turn in the way to the fabric and the stitches can have less tension problems. I have both types of machines and yes, the vertical bobbin assemblies do a better job at FMQing IMO. This is why vintage machine lovers enjoy their 221, 301, and 15's so much. And why I love my old Berninas and Pfaffs.
What she said. They also do better with embroidery. The Pfaffs do move the hoops, but you can use a scythe type seam ripper and cut the thread mess, clean out and fix the vertical bobbin without even moving the hoop. Works the same way for almost every other type of fabric jam, like fabric drawn down needle hole.
One big disadvantage can be a thread cutter. They don't always work right maybe because of that one less s turn.
I've had a couple of drop-in bobbin machines, and except for Brother/Babylock buttonholes, I don't want another.