Speaker Amp Pairing Question

Hi,

Im relatively new to the world of hifi audio and am in the process of setting up my first system.  I've decided to go with Wharfedale Linton Heritage speakers.  I got a good deal on a Schiit Aegir amp so that's what Im planning on using.  I have a freya + on the way as well.  My question is will one Aegir be enough to power these speakers sufficiently? I typically don't listen at super high volumes, but I do have a relatively big room with 12 foot ceilings. 

The specs for the lintons are as follows: 
Nominal impedance: 6 ohm
Minimum impedance:3.5 ohm
Sensitivity 90db
recommended amp power 20w-200w

Aegir : 
Stereo 8 ohm - 20W
Stereo 4 ohm - 40W

Also wondering if the ohms is a dynamic thing and at which level the amp/speaker pair will generally be running? will it be closer to the 8hm at 20w most of the time or 4 ohm at 40 w most of the time?

Any input is greatly appreciated