Range for a 5.8GHz Cordless Phone?

do not buy that buy a 900Mhz phone that is better
i have a 5.8 GHZ phone which does not even go for 50ft

ame-link.com/adp-5000.htm nice phone Range - 3oo meters out doors and 50 indoors, have not found a stronger phone

yes the Ame-link is nice,but I found it difficult to hear about 80% of my calls. not enough volume control.Toobad they put more effort into the colour screen and crystal clear elevator music ringtones from the external speaker.I was hoping to get something new that was not in every house in the neighboorhood,and unaffected by my wireless router.