or you could get an Image Dynamics IDQ for a better price with close to better performance

These are questions you really should be asking your installer. I am assuming that you will not be installing these yourself from the questions you are asking.

I agree with the general sentiments expressed by everyone who has posted in this thread prior to me. I for one do not like JL audio subwoofers or equipment in general so the idea of using JL audio subs does not appeal to me at all. However, your question was not what does everyone thing about two JL 12W7s in a Z? Your question was will they fit? The simple answer is yes. They can be made to fit. I don't think they will remain in the corners of the hatch so much as to take up the entire corners and most of the rear hatch due to their size and the amount of airspace that they require.

To answer your second question. No, they will not fit in the OEM location without some extreme modifications being done to the rear deck. Not to mention it will be VERY VERY difficult to make it sound good in that location. Anything is possible with a good enough installer but the questions you have to ask yourself is, am I spending my money wisely? There definitely are much better options available. Good Luck either way.

The W7 was about 350, the 1000/1 was 390, and the box was 200. I saved a lot of money by doing the install myself. I reused wiring and a two channel amp from my old car to save some additional money.

I'm gonna be honest part of the reason I picked the W7 over some of the other woofers that supposedly sound just as good for less money is because it looks incredible. I justified the extra cost by saving money elsewhere. I just didn't like the appearance of the other speakers. I know... It's shallow.