What's the difference between the various lost phone apps? I want to get a security app for my phone. I mostly need something in case my phone gets lost or stolen.

Researching this I have found several apps:


iTag
WaveSecure
LookOut


I am sure there are more out there too.

My question is why would I choose one of these over the others.
How do they differ? Does anyone have experience with wiping or finding a lost phone using one of these devices?

Thanks!
I suggest LookOut.  I use it and it's quite good.  It also has the virus scanner and backup of data.