I know that the smaller single speed Avets have aluminum-bronze alloy main gears. I have not had my SX long enough to test the durability of these gears. I am going to buy another LX or JX reel this week and may buy the 2 speed just so that I can have stainless steel gears in it. I would like to know if anyone has had any problems with the alloy gears and how durable they may be over the long haul.