Gentlemen Let me throw some Light...
A submarine (Diesel/AIP) Depth Limit 300-350 Feet is Queen of Under water.
In Indian Ocean water is Saline Magnetic Anomaly Detectors are of no use below 500 Feet.
Sonobuoys are of no use below 600 Feet. (Both these figures are for Warm waters)
Under Sea Lanes have been mapped by All Nations Big and Small. Each Navy Has Oceanographic Ships. Each Nation knows from where your subs will come...When ? No Clue!!
Incase you have A SSN OR SSBN which can dive below 500feet, you are King of Seas in Indian Ocean. Else, you are a toast to P3Cs, TU 142,P8,Do228, GBU1000, Magnetic Depth Charges...Russians made Nuke subs in Cold War, in Cold Water the detection Range of SONAR,MAD and Sonobuoys is more than warm water as Density increases...But Ruskies took a Big Risk against Yanks for Carriers.
Pakistan by buying 8 Subs is playing a Russian Roulette...These Subs will be independent, where as Surface ships are more prone to attacks.....
If Indian Navy Goes for More SSNs then the Game will be Other-ways....
If we induct more Scorpene, then you get me first or I--Game is Neutral...
Pakistan has got very WELL Trained Naval Crews..."Sun Tzu Never Consider your opponent Weak"
Some thing which I dont feel Comfortable is Chinese Hardware is High on Maintenance, Hope No Submariner dies in a Suffocating Tin Box.
Let God
Ares give Strength to Men in Arms..