Realistic is the only way to go for me.
The graphics in this game are extremly impressive and lend themselves well to making this game as immersive as it can be. All characters in this game move fluidly while performing any action, be it leaning around cover or window breaching into a room, and the detail on your team mates uniforms is impressive. The weapons look excellent aswell, many times i found myself attaching and then detaching the silencer just so i could see the weapon model. Lighting is also great in this game, the rooms filled with slot machines and neon signs look particularly good. All this really creates the feeling you are in Vegas
Sound effects are unbeleivable. The boom of gunfire is deafening and the crack of flashbangs is really satisfying. I have no idea what the music in this game is like, because with every game i play, i turn the BGM off so i can hear the ambient noises and sound effects, eg. the whistle of the wind through the window broken by gunfire on the top floor of the vertigo tower or the jingles of the slot machines in the Calypso.
The Gameplay is extremly fun and addictive if you like tactical shooters and to me this game is undeniably the best in the series, and although some people may disagree, the whole point of the Rainbow6 series is to be an elite CT squad, and this is the only RB6 to date which has pulled that off beleivably. Using cover is neccesary in every level and at every battle and this adds alot of tension to the combat. You really begin to get nervous when you can see enemies moving postions or trying to flank you, but you cant do anything about it because you are pinned down by other enemies. And they will pin you down, and move around to flank you because the AI in this game is smart. They use cover just as well as you or your team and with their considerable numbers they make the combat seriously intense and rewarding.
I would recommend this game to anyone who enjoys a challenge and a good FPS or tactical shooter. I would also recomment playing on Realistic because this game deserves all the effort it takes to finish this game on that setting.