Anyone have experience with Frobana or similar hand crank sole stitchers?

[Ppolachi]

Hey all-

ive spent my winter learning how to make bespoke shoes, and I’ve gotten good enough at it that people are starting to try and commission me to make pairs for them.  I want to oblige because a) they’re friends or friends of friends and b) people pay insane prices for this type of shoe and i like everyone else have bills to pay. I’ve decided I need to get a sole stitching machine to try and increase my output with time saved not hand stitching. Does anyone here have experience with Frobana, Mitchell, or similar styled machines that can be operated with a hand crank? And, failing that, does anyone have experience with a Landis 12 or similar machine (and if you do, how steep is the learning curve when starting out with those?) ?. Any advice appreciated greatly, will pay it forward many times over.