If you run a set of ZEROs (www.zeroimpedance.com) then you can run any tube amp you want that makes the needed power.
Here are some comments regarding the ZEROs, with a tube amp that isn't otherwise comfortable on four ohms:
http://www.enjoythemusic.com/magazine/equipment/0703/midmonth/atmazero.htm
Here are some comments regarding the ZEROs, with a tube amp that isn't otherwise comfortable on four ohms:
http://www.enjoythemusic.com/magazine/equipment/0703/midmonth/atmazero.htm