picking a sub

I am currently trying to figure out a new sub/amp combo for my new car. It is an acura integra hatch back. I have room for a 3.5 cuft ported box and am looking for something that hits really low and can be felt. I am not really looking for something that will be ear piercing loud just something that hits hard down low. I am looking at a single 15 inch RE SEx sub because I can get the sub and amp for reasonably cheap. Are there any other subs out there that I should consider that are realitivly cheap that will do what I want? Thanks for any advise in advance.

What do you class as 'cheap'? One persons cheap isn't another.

its a hatch back... you could have a leprechaun farting into a KFC bucket behind your seat and it would hit hard and low. i see nothing wrong with that RE, i run an SX18 myself, but if you want it to hit hard down low then you need to tune your box low. you might sacrifice a little loudness overall but you'll be checking your pants after you hit those low notes. what amp are you planning on running?

Look at this if you want low and hard. Here are the application notes that give example enclosures and describe the response.Dodge Magnum in progress:

Pioneer DEH-80PRS - PPI Amps - Dayton Subwoofer(s) - Exodus Anarchy's - Vifa Tweeters - Kinetik Battery

Thanks to all your advice. I really like the "leprechaun farting into a KFC bucket" it made me laugh. I have already ordered a sub/amp and decided to go with a 12 inch RE MX with a 1500 watt RMS amp. Hopefully this should do what I want it to. Also about tuning the box to a lower frequency, RE recommends a 2 cu ft ported box tuned to 32 HZ for this sub. Can I tune it to mid to high 20's without hurting anything?

What are you leaning towards spl or sq?Dodge Magnum in progress:

Pioneer DEH-80PRS - PPI Amps - Dayton Subwoofer(s) - Exodus Anarchy's - Vifa Tweeters - Kinetik Battery