It somewhat depends on the sound level you hope to achieve.
An increase of 3 db requires a doubling of power, so it can add up fast. I have a buddy who clips his Bryston 14B-SST into a set of Vandersteen 2Ce's on an alarmingly regular frequency. WAY too loud for me, but not apparently for him.
One issue with speakers that run down to that 2-4 Ohm load is going to be supplying enough current at raised volumes. Finding an amp that will handle the load might be a more important task than looking at raw power numbers.
Uncontrolled (hard) clipping kills speakers, not high power amps - unless you are pushing them beyond their maximum SPL output limits.
Whatever you use - it'll need to be a biggun'