i'm using a wharf 9.1 (86db/w/m)* with a 12watt amp and it goes uncomfortably loud without distortion, my listening area is small though. Most of our music listening is done around 1-5watts, So as far as loudness is concerned you'll be okay.
*at 85db the Permissible Exposure Time is 8 Hours a day before hearing damage occurs, according to NIOSH