Had played about 1/4 of Far Cru when I first got it years back but then shelved it for whatever reason. It wasn't due to it being a bad game as I really enjoyed it, just some other shiny game came along. Finally got around to finishing off the rest of it and have now done so.
The island setting was a nice change of pace from most corridor shooters. Levels were mostly open so you could get to your target using multiple paths. Besides the arsenal of hand weapons, there was a good amount of mounted weapons and vehicles to drive. Decent enough AI for the levels too as the enemy would hunt you down if they heard you and would try to use cover.
Even on the island there was a good mix of different settings. From thick jungles to the beaches, rivers to swim or boat in, hidden army camps and underground bases. There was also a good use of altitude as the island has many mountains. At first it was like stumbling into a South Pacific island camp of mercenaries. Then later it became the Island of Dr Moreau.
I preferred the mercenary fights over the mutants but still didn't think the mutant sections were to bad. Think this held me off on playing the game as I heard many people quick at this time, which was where I first stalled at. After finishing it up, the mutant parts were small and more mercenary battles returned later. Only the last 2 maps were full of mutants and these were the 2 maps I didn't like when compared to the rest of the game.
The island and its hidden bases had a nice sense of exploration as I was unsure what was around each corner or behind every tree. Occasionally I'd stumble across ancient ruins on my way to a high tech base buried underground.