What works best for you is what is better. It depends upon your convenience, propensity to learn better and where you can grasp your lessons well. However, owing to the latest trend, people are going for online classes more than the traditional offline ones and this is understandable. You get to save a lot of time in online classes and the comfort of being at home and efficiently preparing for your exam without going through the hassles of conveyance and getting ready for the offline coaching centre. Hence, online classes are unequivocally more comfortable and chosen alternative. However, you should determine what is comfortable for you.