Its a good thing you came here asking because buying a meat grinder, IMO, is something you should research a bit before you buy. The same applies to a stuffer or a mixer.
The sam baere grinder, most dodels, appear to have the headstock and feed screw made of "durable die-cast metal with aluminum alloy plating". The indusrty standard is stainless steel. There is alot of friction and pressure on these parts and I think stainless will hold up better and be easyer to keep sanitized.
Try to get the most powerfull grinder you can, its better to have it and not need it than to need it and not have it. Look for or ask about lubricated gears made of iron or steel, stainless steel headstock and feed screw, #12 or larger head.