Last winter UI bought the new slim alpine subs. they sounded great for awhile but the surface dents very easy and I had a problem with them Blowing. They just dont handle loud very well I guess. Yesterday I bit the bullet and upgraded to the JL13tw5's. My shop that does all my work gave me full credit for my aplines so the price difference was decent. The jl are way louder, sound better all around. These things ROCK. I have read that the shallow jl wont do well with low end but the ones in the titan do great with all bass. there expensive but I am putting them on my recomendtion list for sure. There in there own boxes right now and will be having a custom box made as soon as I can be with out the truck for a few days, so there only going to sound even better