Hey, This is probably a stupid question, but what is the difference between watts and ohms? I am looking at two Ashdown 410 cabs. One is 300 watts at 4 ohms the other is 450 watts at 8 ohms. Both are the same money, $299 no tax or shipping from Zsounds, is there a big difference? (for the time being I am going to use an old 200 watt Carven head to drive it.) I am thinking of the 450 watt option. Any advice? Thanks.