MSCM guns - usage / problems?

We are using the 9190G and have 10 months to go on our 3 year service contract. We are quickly seeing more and more guns with issues:

trigger not functional
screen jumping
IP address dropping randomly
cracked screens (three different guns!)
and sometimes just not picking up the wireless signal

I'm curious as to what everyone else is using and what issues you've seen AND when in the lifecycle did you see them.  We had trigger issues very early on and then about a year of clear sailing.  The past 6 months have been brutal though - we seem to have guns out for service all the time.

We like the 9190G model because it has both numerical and alpha keys on the keypad and you don't have to switch between modes.

Your thoughts?

Thanks!

Michelle