I am going to make myself a home stereo sub. I have already bought the crossover components. I calculated it for an 8 ohm load.

I need to find a good sub, either 10" or 12". I was thinking of using a Car sub, has anyone had any experience with this? If I do that I would have to get a 4 ohm resistance so my crossover will still work at the frequency I designed it for.

So, back to the question:

Which sub should I get, please keep in mind there is a reason I am making one as opposed to buying one (cheap )