I really like lower-powered variables. A Leup 2.5-8 or Conquest 3-9 are super on the low end and hey- if I want 6x or 4x, that's there too. My main thick-chit rifle has a 1.8-5.5 on it and it's set around 2x generally.
I have had a couple variables that were wonky but it was the classic "Leupold shuffle" where they wouldn't shoot a box test to save their lives. I don't think that had anything to do with being fixed vs. variable.
A fixed 6 is not interesting to me... however, when you mentioned later it was for a kid's first rifle that kind of changed things. For that, a fixed 4x does make some sense; less to fiddle with. Or a fixed ER scope with lots of eye relief like a 3-9 Conquest. The massively variable Leupold eye relief is confounding to kids; I've seen it first hand as my daughter cranks up a 2.5-8.
