It's not a problem if you don't have time to read the book. I have yet to see any proof that the CIA isn't a Micky Mouse Operation. I'm doubting that they have a secret history of success that has been hidden from us, but I'm an atheist who doesn't put blind faith into things.
You don't need blind faith. The CIA has had big public successes in the recent past. The tracking down and killing of Bin Laden was a CIA led effort. The CIA also knew very well where Bin Laden was before and after 9/11, and was responsible for tracking him to Tora Bora. The only reason that ended up a failure was due to the military and its unwillingness to commit the troops needed at the CIA's behest.
Overall, you can't expect an organization like the CIA to survive without proving its worth. The nature of the CIA also means that its successes are unlikely to be known to the public, as intelligence gathering and covert operations are, by nature, continuously progressing. Only when the CIA does something wrong can you expect stories to be published. To say the CIA is overloaded with failures is, in my opinion, a very blind and narrow view of the situation.
On the point of the KGB, its not surprising if they come off as superior. The Russian's have the longest, most continuous, and most successful intelligence and covert organization history in the west and possibly the world. They have continuously had active intelligence organizations dating back to Peter the Great, whereas every other major western power (including the US) only really cared about intelligence during times of war, despite the history of failure due to this. It wasn't until WW2 that the US and Britain committed themselves to a strong and everlasting intelligence effort.
Lastly, the vast majority of intelligence efforts is banal. Intercepting daily cables, collecting information from diplomats, tracking the movement of military units, government officials, and various other targets is the mainstay of any intelligence organization. Running coups, covert operations, and other hollywood style actions, no matter how many examples there are, is a small amount of what they do. Thus, the ultimate success of any intelligence organization just isn't going to be written about.