I attended the What Hi-Fi show at Novotel in November. They (Dali) had their Ikon 6s running 5.1 off a Denon - I can't recall the model, but the new 3808 comes in at around £1k if that helps. It all sounded quite blissful running the 'Happy Feet' opening scene.
I'm running the Dali 6 5.1 package of the Onkyo 606 and am very happy with the sound. Will be upgrading Amp in a year or so I expect so will be interested to hear the difference if it's considered that a beefy £1k+ amp would be essential.
The Ikons are capable of functioning with as little as 25 watts and have a Sensitivity rating of 91.5 which is above average.
So, I don't think it is so much raw power that you need for these speakers, as it is a solid power supply combined with an amp with lots of tight control and subtlety.
Consequently, I would go with a slightly better than consumer amp, and yes, amps in the £1000 range would get the job done. Though you could get buy for slightly less than £1000.
Though I think it would be wise for you to set some budget limits or at least a budget range so we can narrow in on proper AV amp in your price range.
Certainly the Denons would be good. Denon models are in transition now, moving from the xx09 models to the xx10 models. The AVR2809 and the AVR2310 are in this price range. As are the Marantz SR7002 AV, and the Yamaha RX-V1900.