I guess it all comes down to what you're trying to accomplish.
If your main concern is quick access to your gun in an emergency situation and you want to eliminate the possibility of encountering weak or dead batteries, a simplex lock device makes perfect sense. It's not easily defeated.
On the other hand, if your main concern is that your teenage kids will go to great lengths to break into their father's gun safe, then perhaps there are better solutions than a simplex lock device. But I'm not convinced that someone with plenty of time and determination couldn't break into a Gunvault.
Most people who lock up their guns are protecting them from theft by burglars or from young children who may happen to discover them. The very best solution for this is a full size gun safe such as something from Fort Knox.
FM, I don't consider this thread a flame war. I respect pytons opinions, and he has made a valid point. I just think that his situation is an unusual one and that for most people, a simplex lock is just fine.