It looks like there is an new lead free option, although I don't know if it is available in North America. The difference between this one and the others is that it has a dual tin core. The front being soft and frangible, while the rear is hard and stable. There is a Partition-like barrier between the two cores. Interestingly the front is "specially pre-fragmented". This seems similar in principle to the Berger hunting bullets - fragmentation creates very large wound cavities - but also retains deep penetration ability like the monolithic and other premium designs. Norma's new Kalahari bullet and RWS's Bionic Yellow are also designed to function this way.
http://rws.tollwerk.de/en/hunting/products/rws-centerfire-rifle-cartridges/Product/show/evolution-green-bullet.html
http://rws.tollwerk.de/en/hunting/products/rws-centerfire-rifle-cartridges/Product/show/evolution-green-bullet.html
