Far Cry was cryteks best game ever!
No crysis can reach up to that playability that FC had big maps not linear, i played it several times all in different ways.
Crysis was also good in thos ways to play, Crysis 2 was good and fun so game was worth the money in single mode only, BUT to linear.
If you really care about an open world I can only say one thing... play S.T.A.L.K.E.R, it destroys ANYTHING that Crytek has ever made

Im on metro now , but i recently bought the whole stalker serie;-)