Does an electric grill make it faster than a pan?
They are different tools.

The main problem with an electric grill (two sided) is that is has a lot more parts and pieces that can break and is harder to clean.

The other big problem of an electric grill, is that it is mostly a single use tool compared to a frying pan that you can use for a ton of different applications.

For example, you want to grill some chicken breasts, you can do it in a pan and in a two sided electric grill; but lets say you want to make a sauce/gravy, in the case of the frying pan, you already have the tool to do it, in the case of the grill, you will have to use another tool  (pot or pan) to do it.

As for the cost, here, in Canada, you can find cheap ones (foreman grill) at around 30$.