Car Stereo

I am looking to update my car stereo system. right now, it just has the standard stock items in it. i think that i am going to get a new deck, two speakers and maybe a sub-woofer. but i dont know if a the sub will be unnecessaryily loud in my small crew cab pick-up. what do you think?? should i just go with the deck and speakers, or should i add the sub as well?? thanks:-)

I would add a subwoofer it adds a lot more depth to the sound.look into jl, and solar barics..im sure you can find a small one that wouldnt cramp up your cab.