1 1200 watt 12 inch sub or two 500 watt

what would be a better choice one 1200 watt max 12 inch sub or two 500 watt max 12 inch subs?

I think you're looking at the wrong numbers.

give us the RMS power loads, ohm ratings to go with each RMS rating, the amp you're using, and its abilities.

THEN we'll get you squared away

the one is a pioneer dvc 2 ohm 400 rms and the other two are rockford fosgate p212d2 250 rms powered by a mtx tc4001 mono amp 400 rms 1200 max at 2 ohms

and what kind of system are we shooting for?

SPL, Just loud as balls going down the street, or just trying to find the bass that your door speakers aren't giving you?

And last question, what kind of system are you trying to put together?  Loud or musical?

As to your choices above, I'd take RF over Pioneer any day of the week, but depending on what you are trying to accomplish with the system there may be better choices than either one.

I'm gonna agree with DYohn there...

to be blunt, i'm not a fan of either of those subs, but I do understand working with what you have.

I had pyramids for the longest time    but that was because I was being a cheap ***

as loud as it can be while sounding decent i already replaced all the other speakers in the doors and rear deck with some kenwoods. i am just adding subs now to complete the system