My 2 cents, as someone who doesn't have an industrial machine but has made and fixed a ton of misc gear on a sewing machine from holsters to pouches to curtains for our house at this point I think the best place to start with is a Singer 15 clone. I see a lot of love for the 15-91 specifically out there. There are many related models out there from the original singers to the Japanese models that came along after WWII when the US reportedly gave them the patent to stimulate their economy. I have a Japanese one (same machine sold under many name badges but mine is a morse) that I paid 50 bucks for out of the back of a guys van and it has paid for itself 20 times over. Would love a juki or even an older industrial machine but its hard to justify the price for one when I have made 4 saddles and all kinds of other stuff on this little workhorse. Now, if I was making packs or had the advanced skill like some guys on here have I would have something with a lot more capability with a walking foot, clutched motor, serger, all that jazz. It's honestly amazing how heavy duty and well made the old household machines are and a marvel that they can be found so cheaply for such a quality, strong, precise machine.