Personally I wouldn't get aluminium unless I was racing. In 30+ years of racing on much newer boats we had to replace one complete alum winch and a drum. They aren't very tolerant of running them hard and putting them up wet. These boats winches were rebuilt twice a season. I wouldn't go any smaller than the OEM Lewmar 48ST. We race with a 155 genny and it sometimes take someone to get over it with a two handle.
By the way get this handle, its the best piece of equipment on my boat. A true marvel, make sure it's a double 10". I dropped one overboard once and about cried
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