Nautilus or Virgos?

I'm currently in the process of upgrading my system which presently consists of Theta Miles CD, BAT VK-30 preamp, SimAudio Moon W3 amp, Hales Revelation 2 speakers, and REL Strata III sub. The speakers will be the first to go as I've had them the longest and I am currently considering either the Audio Physic Virgos or the B&W Nautilus 804s (or 803s). The next item to be upgraded would probably be the amp, to a Plinius SA100MkIII. I'm wondering whether the Virgos or the Nautilus would be a better match with the Plinius? Although I listen to a lot of jazz and vocal, I also listen to rock and techno/electronica so I'm looking for something which would give me a very natural and lifelike midrange (which the Hales have) coupled with speed and attack. Also, since I live in an apartment, I'm looking for something which would sound good at lower volumes as well. Your views on the Nautilus and the Virgos would be appreciated. My budget is about $3000 to $5000 so any suggestions would be welcome too.
Do yourself a favour and check out the Spectron class D amps before you change the speakers.The virgos or nautilus are both excellent but you may well be surprised at how good your old speakers sound with a Spectron driving them.Frank.
If you want midrange in spades the virgo's are the way to go. Slightly polite in the bass but can be played soft to very with the speed and attack, which you seem to be looking for. Because of their smaller size they work well in smaller rooms.
I have the Virgo's. They have to be brought out into the room to get the three-dimensional disappearing act to work. Their midrange is perfect, and they actually make you feel like a person is in the room with you. Very clear speakers. They are nice in that they are small and nice looking. I have driven them with Denon 200W monoblocks, Sonic Frontiers SFM-160 monoblocks, and an ARC VT100m2. The tube amps sounded much better. My only complaints about them are the room placement, and that they are a little shy in the bass.