My understanding is that India's BMD is actually the Israeli Arrow-2, integrated with an Indian rocket. The Israelis provide the core components like long range radar, control center and kill vehicle. The reason for this is because back in 2002, the Americans blocked the Israelis from selling Arrow 2 to India.
The Green Pine radar used by the Arrow 2 was sold to India with US approval, and was deployed in India in 2001. In early 2002 American officials sought to stop Israel from selling the Arrow 2 interceptor missile to India, arguing that the sale would violate the Missile Technology Control Regime.
http://www.globalsecurity.org/space/systems/arrow.htm
If I was Indian I would not be happy with my government's decision to purchase Arrow 2. BMD is a rich countries' game because the same amount of funding can buy you a lot of ballistic missiles of your own.
Also, BMD systems like Arrow 2 are extremely limited in operation. They can be defeated by decoys, which are not difficult to implement for the attacker. They can be saturated by many rockets fired at the same time. The radar often doesn't detect or track properly. The missiles are very limited in range. You can protect maybe your headquarters but you can't protect your troops in the field.
I don't know if Pakistan has decoys on their SRBM.