Never played a Far Cry game before so wasn't sure what to expect, but after playing this for a few days I've got to say it's absolutely brilliant.
Spent absolutely ages doing all the radio towers/outposts/crafting every item without even looking at the main story, think at one stage I had 18 skill points waiting to be used but everything was still locked!
Got a few of the signature weapons too, Shredder is awesome. Current weapon choices are:
M700 sniper with silencer and scope
The Shredder (silenced vektor SMG with silencer, extended mag and reflex sight)
The Bull (M133 shotgun with extended mag and reflex sight)
Grenade Launcher
Done a few missions for Buck so far but have done pretty much everything there is to do on the first island, hoping that I unlock the second island soon.