Plots always bring you more returns than apartments as there is no depreciation. But if you are planning for a home loan, you will get only 50% of the total cost if you are buying a plot. Also you will not get tax benefits for home loans taken against land purchase. But these are just two aspects of it. In terms of investment plots are always the best choice. Also, due to high demands, it is difficult to get an ideal plot if you are planning to but in cities like Delhi and Mumbai. But there is a lucrative option in suburbs of big cities.
In terms of capital gains a plot is always the best choice. Apartments can cause depreciation in a long run and maintenance costs are also associated with it in a long run. But the demand for land will be always there. But while going for land you should ensure that you are investing in a good residential locality or in a place where there are chances for development in the near future. Plots in gated communities will be ideal. If going for an apartment make sure that you are buying from good and reputed builders only, as inefficient construction can cause troubles after few years which will increase your maintenance costs.