You may be deciding based on RE bull period of 2004-2008 when there was lot of construction & prices increased 2/3 times.
To assume that toll-naka will be next kandivali-east in 3/4 years is far a fetched thought.
Frankly speaking it is not worth 4200 psf due to noise and commotion plus away from station.
After spending 47L I would want peace of mind in my house.
If you work in Mindspace, malad then why not rent at kandivali/borivali?
What advantage you see buying in this project right now?
I see neither price or nor area attractive.
For long-term investment point you can certainly look at Panvel.