Perhaps more ubiquitous than crows, you can find Engineering Coaching Institutes in India in all shapes and sizes, to put it metaphorically. They cater to all sorts of students belonging to various sections of the Indian society. Many of these are more popular than prestigious colleges of the country. This has come to be because of the aspirations of the students from all over India to become engineers, fuelled by parents who want the best for their children.
You need to find out all the information related to the institutes before enrolling for one. This is not only because they charge a hefty amount as fees but also because it is about your career. At times you need to differentiate based on locations. The engineering coaching institutes in Delhi may or may not be as good as those in Bangalore, or vice-versa. Needless to say you need to do your research before opting for any of these.
You also need to know whether the claims they are making are genuine or not. There is no dearth of engineering coaching institutes that advertise falsely about their achievements, that of having placed hundreds and even thousands of students into prestigious institutes such as IIT, IIIT, NITs and the like. You need to be very cautious and choosy when looking to get yourself enrolled. It would be good to cross verify the credentials of the faculty of the institutes before you get admitted. If this is not possible, you might as well play safe and choose the most premier ones.
The engineering coaching institutes in Bangalore are likely to be more focused on preparing students for regional entrance exams, i.e. for admission in colleges in Bangalore and at best south India. The same is perhaps not the case with these coaching institutes in other parts of the country. In Delhi, for instance, there are many engineering coaching institutes catering specific to the IIT JEE. Not to say Bangalore does not boast of the same, but the more successful ones for IIT are in north; the most prominent ones being located in Kota.
So before getting yourself enrolled, consider the factors mentioned above and rack your brains over them. Yes, you need to be very specific about what you want achieved and accordingly plan your enrollment in one of the good engineering coaching institutes in India. So, best of luck with your preparations and give it your best shot. Never forget that it would be your hard work that will ultimately get rewarded and not any institute.