Whats your whole budget? I'm actually looking in the same sub range as you and I'm considering 2 12 BTLs for my trunk. Really what it's going to come down to is how much you are going to spend on an amp. You have a hatch so your space is probably somewhat limited and the single 15 is probably your best bet. The BTL is very loud but known to have decent sound quality for its cl***. Now if you're looking to get just pure loud, and don't really care for sound quality, the DC Level 5 would be killer, but it doesn't sound BAD on music so it's a good choice. If you have around 3-4k RMS, I'd go with the DC Level 5. If you have about 2-3k, I'd look into the BTL. You'll need a high output alternator so that'll cost you around $3-400.
Edit* Why did it star out class?