It's in the description, "Long-time Advantage users will rejoice to learn that we’ve replaced the mushy, rubber function keys with high-performance Cherry ML sw

It's in the description, "Long-time Advantage users will rejoice to learn that we’ve replaced the mushy, rubber function keys with high-performance Cherry ML switches that offer the same low-force and tactile properties of the MX Brown.". Great change but I guess I will not drop 350$ just for that ;)