Is 1 set of components enough?

Hi looking to get components for my truck (ext. cab), I am running a 12" type r  1242D, right now, will be adding a 2nd one later, but first I would like to upgrade factory speakers.  Theres 2 in the door panels and 2 more in the rear doors.  My question is should I  A) get a set of components for the front and not run the back speakers (not sure what size the speakers are) B)  just get components for the front and co-axials for the back. and get a 4 channel amp, or C)  get a 2-channel amp and power the components and run back speakers off Pioneer HU...Either way I will have 2 amps, one for subs and one for speakers.  Im looking at Orion's P6.2 components.. does anyone know much about these?? It says they are 3 ohms, to give you more wiring options... how do u wire these?

oh yeah or option D) get 2 sets of components and a hipower 4 channel amp... Im looking for good SQ to compliment the subs

One set of components is enough.Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

ok, what do u recommend for the back speakers then, upgrade them, or disconnect them? I want a full sound, but not sure if they're needed.

i run components in the front and coax's in the back. this minimizes the backseat passenger complaints

I have to 2nd the componets up front, co-ax's in the back.. Run a four channel for complete sound and decent rear fill, set-up accordingly.