The 259 is more attractive, with grooves giving the suggestion of triple flanges. It's 49mm in the head and weighs 25g. I think this is an acceptable length; definitely on the big side, but I've seen arrowheads at auction and antique dealer websites described as up to 50mm. Still too heavy - but our techniques here should help that.
Mr. Collins describes them as armor-piercing. I don't know anything about Chinese archery, but I can believe it. They show a compact, sturdy cross section with little or no waste, and the tang would combine well with a bamboo shaft, resulting in a very tough, heavy arrow with plenty of momentum in a small area.
Chinese armor-piercer to Persian bantamweight
A lot of work? Yes, admittedly, and attainable mainly because I have access to a drill press at the moment. Also I still can't produce a finish as good as arrowheads that were cast as three-bladed. But if you're in North America and have a drill press available, this is a very economical option.