This is an interesting area and I researched this some time ago as a young parent for my own children.
Most playschools are owned by franchisees and the quality of education is pathetic, however if you are working and need someplace safe to primarily act as a day care it should work well. The problem I found is when these children get into regular school at grade 1 OR 2, they are much behind other kids and struggle.
If possible I would recommend joining mainstream school at the earliest where there is some standard of education offered, choose one of these playschools as day care after mainstream school and you get best of both worlds.
@Papabear, Thank you for your suggestion. I could feel my son is too young to go to main school as he need extra care and safety. We are planning to put him in main school from LKG. So I€™m searching good and standard preschool in our locality.