hi,
IMO - if you should have a little power left, above the 2 kW @ 1 ohm for these four subs - it won't hurt - you'll just adjust the gain on the amp..
the thing is - are you looking for AB class of amp or D class or something else?
Don't have actual experience with these subs, but - a d-class amp . rated @ 2 kW @ 1 ohm, better 2.5 kW@ 1R, should be good = DD M3a (or weaker brother DD M2a would also do the trick).. If you have more than enough juice, there won't be so much stress on the amp..
For better sound dynamics, control, etc, the better choice would be an AB class monoblock, or a very powerful dual channel amp.. But here is the thing no consumer likes to hear - quality will boost price, so the best option is a monoblock, D class, at around 2.5 kW @ 1R . rated from 12V - 13.8 (ignore the values at 14.4V)..