To get price data for a future instrument, is it recommended to use the “continuous Future contract” that are subscribed to my default when calling self.AddFuture(), or is it better to use the price data of a specific future contract retrieved my the future.Mapped property? Take the micro e-mini S&P futures for example: For my price analysis, should I use the price of the continuous /MES symbol or the underlying MES15H24 MES16M23 contracts? Why does the price differ between the continuous aggregated contract and a specific contract?

Also, if the plan is to day trade, thereby exiting all positions before the end of the day, does it matter which of the specific future contracts I select when entering a trade in the future instrument?