In Car terms: Having used all of these at one time or another, Singer, Consew, most others are Chevrolets. Juki is an Oldsmobile (if they still made the Oldsmobile) Pfaff is a Cadillac. Adler is a Maserati. I think the best value is the Juki. The problem with Pfaff is that parts are very expensive. Adler is the best built machine there is (in my opinion), but they are very pricey. Hope this helps.
No one lives forever, the trick is creating something that will.