I had some RCA's from them out of their amp wiring kits and the center pin pulled out of the RCA first time I swapped amps with them.
Ordered some Audtek 18' from parts express for 7.49 and no issues and nice looking cables..
25' is on sale for 6.74
You could fit 2 SVC Dayton HO 10's ported behind that seat no problem..
You would need a amp that puts out power at 2 ohms..
If you had bucket seats I have a nice center console enclosure for these trucks built to spec for the Daytons.
Instead of buying a power supply and using car amps, Maybe you can find the exact plate amp used on ebay for cheap..
Parts express usually has a few on sale as well. might be able to find something that will work through them too.