A problem you can run into is some high powered amps need a bug enough load on the to sound there best. Sometimes easy to drive speakers sound like garbage on a big amplifier as they don't possess enough load on the amplifier. Also generally speaking big amps timing is slower than small amps.
Too Much Power
Please bear with me as I am nowhere near an expert at this type of thing...
I recently read a review of the PS Audio Stellar M1200 mono amps. I was somewhat taken aback by their power rating of 600 watts at 8 ohms/1200 watts at 4 ohms. Made me wonder what, if any, are the drawbacks to that much power? Welcome your thoughts...