No reason to wait for the hearings to give initial impressions. And the hearings will reveal little. Remember, the so-called Ginsburg standard? Now, the Republican senators are committed to not pursuing hard-hitting questions, as that was their position with Roberts and why they cited the Ginsburg standard. The Democrats will attack, regardless of any standard. But you can already tell, from the discussion here, that there's precious little substance in terms of judicial philosophy to go on. That's a fact, and certainly worthy of comment now.
If Miers appears competent and appears to have a judicial temperment, she will be confirmed, unless a smoking Roe gun is found. Her lack of ideoglical bona fides simply will not matter. It won't affect any or very few Senate votes, and might gain a few.