If it also had a socket, it would be nuts.
My Manticore has a 100% crit damage with 2 sockets and around 291Dex. =/
It has vitality instead.
Its either socket, or lph, or lifesteal, or vitality. There is just one random stat on this item.
Socket is most profitable out of all. Similar weapon with 850+dps, 60+% crit and socket will be the same 5m on ah, but it will net you 3-5k more dps, depending on your stats.
Similar weapon with dexterity instead of socket(i.e. with 300 dex) will be significantly worse than one with socket.
Anyway, why not to use echoing fury with ~1200dps 50% crit damage and dex? Should be worth the same 5kk.