Most of the resistance in a cars' wiring comes from the solder joints themselves. Bullet plugs mean you have one joint on each battery lead; Dean's or any other plug means you have solder joints on both sides of the connector itself. In a stock class where people will spend big $$$$ on parts to save a thousandth of a second a lap, this one is kinda free.

As mentioned above, you do need to very, very careful when plugging in your battery with bullet plugs though.

Wire will typically be 12awg for that sort of application.