If you find out hard to drive loudspeakers the best thing you should do it's avoid them.
Today in 2008 a.c.is only the pubblicity that indicate you to buy these speakers.
Today it's esy to find out a loudspeaker with high quality level at 90db/w so use it.
Avoid speakers with less then 90db/w and over 93 db/w.
Only in small 2 way speakers is to consider for quality reasons speakers with 87 db/w.
But in 3 way design is true what I told before.
Others solutions let you throw money and get always insatisfaction loooking for the right amplifier.