What is a good subwoofer that has more quality than loudness as well as an amplifier to compliment it?

I have a lexus gs430 that has 4" speakers with a stock subwoofer. The previous owner has blown the sub, so therefore there is absolutely no b being produced from the 4" speakers. I am looking for a subwoofer as well as an amplifier that will have enough b to bump to but won't overtake the output of my stock 4" speakers. I have looked at a few subwoofers already and like JL Audio, Polk Audio, and Rockford Fosgate the best. The one I am leaning towards is the JL Audio 12W3v3-2. I would like your opinion on this sub as well as if you have any other recomendations. In addition to this, I will need to know what type of subwoofer I need. Thanks!