weather Kelvin institute is good or bad is not a question but if you are looking for institutions which really have helped with admission in AIIMS over the last few years and Aakash and Allen tops the li

after all it is up to your own preparation and also giving regular mock examination helping you with your question selection and time management skills which will help you greatly in your aiims examination

think less about the institution and more about your own preparation and how you get across your lessons yes kelvin is a decent institute but there are better ones as well as every suggested by me