the main reason why some people dont like caps is because of how fast they discharge under heavy use.. they then become just a link in your system not realy doing much but reading voltage.. they take a small period of time to recharge after they disipate.. (prolly spelled wrong...lol) they are mostly used in small setups like your using single subs or 2 small ones.. many people who compete in spl comps use them for their instant discharge for what is called burping... more or less they play a set bass note that their system is tuned to for max spl.. being that they are only using it for a few seconds it gives them the instant power that they need... i am a fan of power cells.. they are like a battery but they hold much more stored current designed specificly for car audio.. they never let voltage drop before releasing current it is a steady supply just like a battery... i install those for people who run multiple amps with large current drain. one of the best things you can do to help your charging system and keep your current at max is upgrade your ground wire at your battery.. most people forget to do this when they run a system then they get the dim lights and so on.. what i tell my customers is whatever you are pulling from the bat you most ground it as well.. so if you ran a 4awg power then upgrade your gound at the batt also with an additional 4awg.. the factor grounds are always small and not great.. every car i own i always upgrade it even if im not running a system.. also there is called a engine grounding kit, more or less it is a whole bunch of wires connected to various parts of your motor and then to ground to maximise your ground.. and believe it or not most people gain hp from doing this.. not anything huge average gain around 1-2hp. but everything in a car needs power, the better the ground the faster it will charge... also i have seen a lot of do it yourself people not make a good ground connection at the amp.. make sure your ground is less that 16inches from amp to chassis and scrape the paint off the surface to maximise your ground..

hope all this was helpful, and im sure iv said a lot of things that most people already know on here.. but its what i do for a living so i thought i would share..

also caps are great for small systems so dont let anyone tell you that it is a waste.. but if you go with multiple amps then look into a power cell from a company like kinetic or stinger.. have a good one man.. happy installs!!