It is a very different experience in both places. Tokyo is dense but organized; everyone follows the rules, so it flows. India feels much more chaotic and intense because the infrastructure is different. If you look at the raw data, it is actually quite surprising. I was comparing the population density of Japan vs. India on Georank recently. You will see that while Indian cities are crowded, Japan has a higher percentage of its population squeezed into very specific urban corridors because of the mountains. The stats might help you visualize what you are walking into.