>(2) Is there any other palm pilot os based device more rugged and robust that Visor ? Or at least any special case to protect the palm device considering that people using them is walking in the streets permanently ?

There is quite a market in aftermarket cases, including a titanium case. Pretty rugged, but pricey. Look at www.visorcentral.com for reviews of various cases for the Visor (and lots of other Visor information as well)