A good clean 110 watts rms crossed over around 100hz should make them rock! Mids and highs don't require as much power as lows do. Do you already have that amp? If so try it for a while.
i have a 4 channel soundstream that is rated at 90 watts per channel rms at 4 ohms and using the 1 and 2 channel for in the boat. soundstream said it will play around 110 watts rms at 3ohm.
I dont think that you will be disappointed with 110W's rms, but they will deff take more. Setting the amp up right will make a huge diff, does the amp have a High-Pass setting?