In reply to Siobhann:
Last winter I had the opportunity to climb with Quarks, Nomics and Ergos on the same day, on the same route. I am a modest water ice climber, leading 4, but have climbed harder, may be seconding 5+ / 6-.
Personally I found the Ergos, unless your on steep, technical ice / sculptured with all sorts of nasty nonsense quite hard to use. You need to continuously flick the pick in, which on steep ice (Vertical) that is smooth (ish) or un-featured can be difficult. I found after the steep featured ice when i was tired they be came quite difficult to place, requiring continuous thought and control. You might argue you need that anyway with this level of ice climbing, but as a modest climber I found this quite difficult and often felt very precarious on easier transit section.
In comparison the Nomics on the same climb were easier to use, less tiring and more forgiving. On the steep featured sections I found slightly more pump than using the ergos, but on the easier sections they were easier to place. You still require a defined controlled flick but they are much more forgiving in comparison to the Ergos.
Quarks on the same route, quite trying on the steep / vertical features ice, much easier to place when tired (i.e. wild swinging!), but generally more pump on longer pitches. Much more forgiving when tired than comics and ergos.
My thoughts!
Ergos: Out of my league! If I was just climbing vertical featured ice then may be, but for me if there is any slack ice in-between I would want to use Nomics.
Nomics: Really good, excellent axe, well balanced and forgiving / easier to placer and reduces pump on longer steep pitches.
Quarks: Really good axe, I still use my quarks for general routes, where the terrain runs between vertical / steep to slabby ice and transit pitches (snow etc.).
I have also used BD Reactor, also a good axe, but I just never got comfortable with them. Not sure why. I used it for a season and one day switched to the quarks and never went back.