The tool you want is the PB Swiss PB 186 M.
This is the classic "hard handle" bit driver they have been making for years, and there are none better!
If you want a ratcheting model, then there are other options out there, but for a simple durable bit driver nothing will beat the PB Swiss.
In years gone by, I might have said that the Snap On had the edge in greasy environments, but they havn't offered a regular bit driver for some years now!
Don't get too hung up about warranty. Get the tool, inspect it, and if you see a fault return it. I doubt you will, I've bought hundreds of PB Swiss tools for myself and various firms I've been involved with, and havn't had a problem! Unless you try using it as a truck tyre lever, you won't either!
What if it 'develops' a fault? Mate, it won't! It's a bit driver made up of 3 components, there won't be a problem! What if you break it? Well, that's 'Tufska Shitski' as they say in Russia! No warranty covers people over stressing tools, although many seem to think it should!
Buy one and enjoy...!
Edit - just realised this is a five year old thread! Comments still stand though!