I had used PPO Box for ordering a OnePlus One smartphone from USA.
They promised 5 day delivery but I got it in 16 days. Their cost is pretty high. They charged me around 4500 rupess for a phone that costs$299.
Their service is fine. they reply to emails but were often unable to understand what I was asking. The tracking feature is useless because the details were updated slowly.
They picked up my phone calls 7/10 times.The phone got delivered in perfect condition with no signs of damage. Overall, I would say that only if you have nobody who is coming from USA or what you want is not available in India, then only use this service.