Like mentioned before, it really matters what they are used for.
I purchased a couple knipex needle nose and was PISSED when I saw how flexible they were. They make different types of needle nose, so pay attention to serration, lengths, etc. I then did more research and purchased a set of Klein Jorneymans. They have no flex.
Before sending the knipex back, I decided to test them against the Kleins. Surprisingly enough, the flex IS GOOD in the knipex. Because of the flex, the knipex actually grip most smaller items BETTER than the Kleins. I ended up keeping them and actually use them as much or more than the Klein. It boils down to this...
Smaller stuff- Knipex (nicer in hand, lighter, get in more places). Again, Knipex makes many different needle nose, so pay attention to what you order. I like my set that has crosshatched serrations. It is a slightly "heavier duty" needlenose than most the other Knipex but still has plenty of flex. I also have a set with only straight serrations but this is much more flexible than the crosshatched set.
Heavy duty stuff- Klein (well made, heavy duty, no flex)