anyone know anything about car audio (subs)?

kinda off topic sorry

anyway my sub is an Alpine SWR-1242D, it's 4 ohms with 500 watt rms.

my current amp is only 320 rms at 4ohms (it's been randomly turning off for the past few weeks too but thats another story). ive had my eyes on another amp thats 450 rms. would that extra 130 watts make a big difference in sound/power? for another $30 i could an amp thats 500 rms, would that be worth it? also is hifonics a good brand? i know stuff like alpine, kenwood, jl, kicker, and pioneer are good but i've never heard hifonics mentioned that much.

you're definitely underpowering your subs so yes it would make a huge difference if you upgraded to that 450rms amp. If you have the money I say go for the 500 but it's not gonna be that huge of a difference from 450 to 500. I don't have experience with Hifonics subs but reading reviews they seem good for the money. Check out this hifonics amp below which does 475 rms at 4ohms, that would be perfect for your type R sub and it's only $150

 http://www.onlinecarstereo.com/CarAudio/p_23915_Hifonics_HFi1000D.aspx