We've been using the Berkshire model all through our office for over five years since we switched from the last model and we're very happy with it so far.
Physically the phone is robust, being made of a (suitably corporate) grey plastic. The handset is ergonomic and quite slim, and I'm able to comfortably able to cradle it between shoulder and jowl when I need both hands. It's also easy to clean, being free of any mesh or recess where crud buildup can occur.
The IP5000 requires mains power, without this the phone doesn't ring and the display doesn't work. The underside of the phone holds the jacks for the phone line and also a jack for a headset.
The reception on the phone is clear both sending and receiving, the handset is sensitive enough that wrapping a hand over the mouthpiece won't baffle or conceal sound at all. If you don't want people to hear your there's a very handy mute button - you can still hear the person on the other end but they can't hear anything.
Transferring calls is very easy - just hit the transfer button and type in the extension. As soon as you hear the phone ring on the other end you can put the handset down. There's also a button to enable headset mode, volume control, redial and follow on call options.
Through the menu button you can set up contacts with either a full number or extension - a feature I have only used once or twice but it's easy enough to set up.
The display is the best bit however. It displays the number that is calling immediately (as long as it's not international, meaning that you can screen your calls if you don't want someone hassling you.
It also tells you the exact amount of time you've been on a call, which is a great feature for call logging if you're charging by the hour. The time and date are shown constantly at the top of the display
The ATL Berkshire 5000 VoIP Telephone complements ATL's range of voice products. The Berkshire 5000 is ATL Telecom's business class Voice over IP telephone based on the SIP IP protocol that is widely used in todays emerging IP convergence business environment. The Berkshire 5000 telephone has the latest integrated voice and data technology offering high performance and high quality. It is a solution that is cost effective while maintaining the Berkshire pedigree. The Berkshire 5000 VoIP telephone is the ideal business partner in both the SME and SOHO business environments. It offers low cost, high quality calls in a reliable VoIP telephone suitable for intra-office, national and global communications.