"I think they've bought very, very well," Mourinho said.
"They have the money to buy, but they have also the knowledge; they have people in the club who know a lot about football.
"They are players at the top of their careers, experienced but still young.
"If you see their age, their maturity, they are in the perfect moment of their career to go to England - no need for adaptation, no need of work to learn the project."
Mourinho believes it would be an achievement to rank above all his others if Chelsea can win the Premier League title this term.
"I always say that the best trophy you have is the last (most recent) one," he said.
"(But) if we win something important with this group, it will be the best for many reasons."
Chelsea's squad is young, with an experienced core, which includes Ashley Cole.
Cole made a rare media appearance in Jakarta ahead of the third and final match of the Blues' Asia tour.
The England left-back stated his belief that he owes Mourinho for under-performing during the Portuguese's first spell in charge, which ended little more than a year after the defender's controversial move from Arsenal.
Mourinho disagreed with Cole's assessment and is thrilled to be reunited with the defender.
"He is the kind of player that you are always wishing can be your player again," Mourinho said.
Cole has often been subject of criticism for off-field behaviour, but the public persona of Cole is at odds with the man Mourinho knows.
"With me I don't remember one single action that made me feel that he wasn't that professional," Mourinho added.
"He is a perfect player."