This is a great topic. The real issue is more basic than this because life is a great value to most humans. Given the most fundamental realities of our existence is it reasonable that we can choose not to die? Live longer, yes, but not to die? The entire cosmos is dieing. Money also has many short term issues when it comes to even short term human health. There are many ethical issues here.
The ethical thing is letting everyone chose whether they want to live or not and giving them the protection they might need if they are a part of a religious or political group that disagrees with life extension.
Coming up with random number for the "perfect length" of human life is authoritarian, not ethical.
And as Aubrey de Grey has already pointed out at the current accident rate people won't live much over a thousand so even if we're completely ageless, there's always that car crash/climbing accident/choking on food/falling on the stairs/etc.
She is very much in favor of medical progress and life extension, just that it should be done by governments and be distributed equally/fairly (random lottery if necessary).
I can see science fiction book in this - a man goes on a serial murder spree because he's not chosen for life extension, and kills until he kills enough that his number is called out in the life extension lottery. In the end the police walks into the room while he's getting his procedure and informs him he will have to spend 4000 years in jail for murder. ~The End~
But on a serious note - I don't see the point of trying to politicize an already dividing subject.
Our aim should be to make governments accept radical life extension AS A CONCEPT, talking about regulations and taxes before we even get to that point is not only meaningless, it's toxic and harmful to the undertaking.