I used to use the double-needle saddle-stitch thing.
But my god, it is hard on your hands pushing those needles through.
(In this sheath, 362 stitches, X 2 needles = 724 needles to push through!!)
I'd be out of band aids, and blood, & belly up on the floor before I got done doing that there deal!!
Do you use leather finger stalls, or gloves, or??
That's not to say the Speedy-Stitcher is without risks.
About 20 years ago, before I started pre-drilling stitch holes, I was sewing a very thick welt on a holster.
The needle broke in half, and nailed my left thumb to the cutting board about dead center, 1/8" in front of the cuticul.
Then the broken needle pulled out of the handle with the thread still in it!!
So I had to take my cutting board and my impailed thumb, with nylon thread hanging out of it, across the basement and find some nippers to cut the thread off, and pliers to pull it out!!
Eeeeeowwwww!
(It's possible I wet my pants! but! I'm not owning up to it at this late date!!)
Needless to say, I pre-drill holes now!!
Rc