what's the buzz for old timer

I & the wife are still at the stone age with 2 Nokia 6620, nerver had a problem. I saw a touch screen phone, hold it & tough to upgrade.
Now what should I(we) get? I don't listen to music. I use bluetooth headset, GPS would be nice If I don't have to pay for, same with WIFI, camera is worh it, & do phone call.
1= it has to be rugged(I do equipment repair & welding & I carry it in my shirt pocket in a case.
2= reliable
3= has to have dual sim slot & unlock
4= quad band (minimum 3)
5= I don't mind if it not the latest gadget (can be 1-2 years out)

What the one who know more then 1-2 brand thinks? (not necessary the one you use)
thanks wrench