So long as you remain well short of the maximum power output, you should be safe. However, given the impedance dips and the amplifier you may find the amplifier's output may follow the impedance curve. In other words, it may drop where the speaker's impedance drops, and then rise back again, so it's not an ideal situation for this speaker.
I would probably suggest that in this case, bi-ampingis a better option. Use one side for the bass and another for the treble. By splitting the current needed, the amp will perform more stiffly.
Try them out and report back.
FYI: In extreme cases, bridging an amp, and driving too low a speaker impedance can cause damage to the amplifier due to excess current.