Thinking about getting an extension speaker for my GK MB 150 combo amp, I spied a used Bag End S-15D speaker for $299. It's 15-inch and its impedance is 8 ohms, which would work with the GK 150 combo amp. The Bag End speaker is rated at 400 watts, whereas the GK 150 amp only puts out 150. So it seems like wattage overkill, but the price sure is right. Anyone have experience pairing this speaker to the GK 150 combo amp? Anything to watch out for? Thanks in advance.