1k for those 3? bro..i suggest you save a little more then only buy. A normal okok subwoofer..12" would be around 500 including box...and let's say you take a 4 channel amp...that would be another 500. So your 1k gone liao..lol

Yeah..get a front component. Front component means get a component set..6.5" and put it as front speakers for your car. A so-so component set would cost you around 400-500, better ones are around 700-800, depending what you are looking at.

If you have a budget, i would personally suggest getting two amp..instead of one 4 channel amp. Get a 2-channel amp and a monoblock. Like that, there's more power for your sub-woofer later.

Well, if you ask me, i think speakers play a bigger part in making a better sound den HU does. You can take rm500 to buy a decent HU and another rm500 for a decent component set..and i'll just use my 1k to buy a good set with my stock HU, i can say my set up might just sound much better den yours.

Well of course having a better HU for my 1k set will optimize my speakers better thou.