Hello bass players, I'm pretty set on buying this Orange Terror Bass 500W head http://www.long-mcquade.com/products/11437/Guitars/Bass_Amps/Orange_Amplifiers/500W_Bass_Head.htm , switchable at 4 & 8 Ohms but I'm really not sure what to get for a speaker cab... I play with 2 guitarists, one plays an orange head through a 4x10 cab and one plays a 212 tube combo amp, I want to make sure I'm able to cut through this. I'm pretty fuzzy on the whole Ohms thing, and matching heads and speakers in general. Where my head is 500W at 8 and 4 ohms, would that be too powerful for a 400W speaker? Would love some experienced advice! Thanks.