WCollins & Keef
I've never had the KLN94B fail on reception, and also I've never had the Skymap 2 fail on reception.
What I have seen is a load of hardware failures in very expensive fixed avionics, which would not be tolerated in handhelds - the latter generally being purchased by people who are used to the pretty good reliability of domestic electrical goods
I think the key to the widely reported handheld GPS reception problems is the aerial location. If on the unit itself (the usual case with Garmins), it will be shielded by the aircraft much of the time, working perhaps marginally the rest of the time (but you won't know unless you are in the signal stregth menu screen). Attaching it to the top of the front window is a very good solution, I think.