Mauricio Isla is a very well fitted Chilean right back, which has a strong tendency to go up front and cover all the right wing. In Juventus, so as commonly in the Chilean national team, he has played in a 352 formation, as a wing back, but he is also able to play in a 4 defenders system, as a right back.
His main strength is his fitness, that allows him to play from box to box, with efficient marking skills in the deep end, and a remarkable index of 2.8 effective forward runs per match, which makes him a constant offensive alternative. Isla has also made good alliances in the teams he has played, especially with his Chilean mates Sanchez, at Udinese, and Vidal, at Juventus.
Nevertheless, Isla was unable to take the place of Leichsteiner at Juventus, and that is mainly explainable because his passing is not as accurate as one would hope for a right back. His nearly 50% of effectiveness in relevant short passing in the games analysed, makes him an unreliable passer, which would commonly loose possession when pressed by opposition.
In conclusion, Isla is a player that can be very useful for teams playing a direct counter attacking style, like I think Queens Park Rangers will often play (his new destiny in England), but I wouldn't recommend him for possession playing teams.