Which Handheld for In-Field Service Work?

got_lost asks: "I'm trying to work out a mobile (read sub-notebook) solution for field servicing Cisco kit. I looked at notebooks but the cost/weight/battery use just outweighs the features I need. The possibles are Psion Revo & Palm or Visor + Keyboard. I haven't really played enough with these before to know their capabilities. I've also heard about a serial card + TRGpro PDA combo. Anyone care to comment? I guess I need suggestions for a portable (Palm/Visor/Psion) solution that allows serial comms. Ideally the solution would not involve the FS staff lugging a HotSync cradle around . I hope this makes sense and welcome all advice on this topic."