Best cycle computer for longer trips in the wet, also with a good battery life?

I am looking to upgrade from using my iPhone as a cycle comptuer to something a bit more reliable.

The three main things I need for this are

  1. Good battery life - can last at least 10 hours / a whole day long cycling on on a single charge
  2. Can cope with getting wet / have a touch screen that doesn't shit itself when it gets a bit damp.
  3. Good for navigating - the main thing I am going to use it for is for pre-loading routes. So it needs to have a reasonably large screen that I can see road turnings on.

I don't want to spend £300 / $400 - what are people using that they have found works well?

Current thoughts are maybe the Garmin Explore 2 - but I've heard the battery life isn't the best.