Saltwater in pools, even normal levels, are of no issue to pool equipment. A pool chlorinated with liquid chlorine, and even solid forms of chlorine, have elevated salinity levels over that of tap water.
The decision between a liquid chlorine dosing system and SWCG is really yours to make. Are you home often enough to refill the liquid chlorine tank? Do you have a ready source of liquid chlorine? The pump and lines do take maintenance.
The low salt SWCG are only sold in Canada. I suspect there are some areas that must require them. All they are are normal SWCG units set up to run at lower salinity and thus create lesser amounts of chlorine. For your pool size, I believe a low salt SWCG would need to run 24 hours per day at close to 100% generation levels to create the chlorine needed.