These Bulava missiles are not so successful. Only 11 of 18 or 19 test launches of the troubled Bulava have been officially declared successful. However, some analysts suggest that in reality the number of failures is considerably higher. Russian military expert Pavel Felgenhauer said that of the Bulava's first 12 test launches, only one was entirely successful. Despite several previous failures officially blamed on manufacturing faults, the Russian military has insisted that there is no alternative to the Bulava.
The Bulava (SS-NX-30) SLBM, developed by the Moscow Institute of Thermal Technology (since 1998), carries up to 10 MIRV warheads and has a range of over 8,000 kilometers (5,000 miles). The three-stage ballistic missile is designed for deployment on Borey-class nuclear submarines.
Because of the repeated failures during Bulava test launches, some experts have suggested that the Borei submarine could instead be armed with R-29RMU Sineva missiles.
The R-29RMU Sineva is seen as a rival to the solid propellant Bulava SLBM.The R-29RMU Sineva (Russian: Синева, lit. "blueness"), also designated RSM-54, is a Russian liquid-fueled submarine-launched ballistic missile.It can carry four supersonic warheads and is designed to be launched from Delta IV class submarines, which are armed with 16 missiles each.The Sineva missile has reportedly been replaced by the R-29RMU2.1 "Liner" missile in 2012
Borei class would restore the acoustic parity that was in favour of Western SSN force for a long time as no new sub development took place in 2 decades.
Infact the Russian Navy Chief mentioned that with Borei class they would start patrolling world ocean compared to the current Bastion Strategy which was restricted to patrolling in restricted guarded area.
The modified Borei class 955U will have 50 % new equipment compared to 955 class and 20 SLBM over 16 Bulava. This should also have further reduction on acoustic quitening.
US Naval ONI belives that Borei class class is far more quiter than any Akula class the only other Russian submarine quiter would be the new Yasen class.
The Soviets managed to evade SOSUS in good part with the development of Victor 3 SSN which came as a big surprise to NATO as previously Soviet submarine were described as Bellowing Cows and Victor 3 reduced noise level to a great level , in good part thanks to Walker spy scandal.
Right now SOSUS system has been disbanded and used for civilian application.
It was amazing to the extent that it let the Soviet knew how far behind they were compared to the Americans in Acoustics and they could actually compare stuff like their submarine patrol in a selected area and then compare with what Walker gave them and then understand what the Americans knew about it.
But the entire industrial effort to build quite submarine subsequent to Walker information , building many dozens of research facility in acoustics , building industrial base to manufacture machine with high tolerance and low noise , ship yard that can build quality submarine were all Soviet Effort something no spy can give you but have to build on your own effort.
Prior to Walker the Soviet spent money on developing Fast , Deep Diving ,Highly Automated submarine with focus on different designs , materials like Titanium and reactor technology both LWR and high density sodium cooled reactor post walker a lot of effort was spent in quitening subs and non-acoustics sensors.
Indian Akula is Akula 1 Upgraded which would settle somewhere +/- Oscar and Arihant is speculated to have Russian Components which could be around Type 095 (Considering 2 Generations behind the Best Russian Technology at the given time).