The phone appears reasonable in build quality and performance, but there are a few quirks that I wish I had known before buying. If you read this, then you will.1 - The display is hopeless, cryptic and virtually unreadable by virtue of 7 segment LCD only being able to display a limited number of characters, therefore N = M, V = U etc etc. I can honestly say that I have not seen a worse display on any electronic equipment in years, far less on something which is supposed to be user friendly.
2 - Following on from that, the Caller ID and the phone list are numbers only - no names (and the numbers are pretty difficult to read, too). Can you believe, they give you a little section of the instruction manual where you can write down your speed dial numbers..... "For convenience"!!!!!!!!
3 - There are two power supplies - one for the handset and one for the base station. Although they are visiually the same, they are different voltages and, according to a little suplementary leaflet, use of the wrong one can damage the equipment. Also, the socket for the adapter is a little dodgy, if you dont have the plug in at the exact right angle, it doesnt make contact.
So, this is not the Panasonic I have long trusted to produce decent telephony equipment.
Could do better - a lot better
When i moved house i needed a new phone so being the lazy person i am i decided to get a cordless phone. Having no clue what to buy i bought the one that was cheap and still modern looking. When i set this phone up i noticed how light and ergonomic(easy to hold)it was. This phone is so good i can go.. 
The Onis 200 handset worked well for 2 years and then failed to
Weve recently moved offices and set up a completely wire free system. Wireless internet access and wireless networking using Apple Extreme Airport base stations. And cordless DECT phones for every member of staff (16).
I have had the twin pack now for a week, and I too have noticed a slight echo and buzzing when using the phone. Looks and handles ok, good features but very poor choice of ring tones/melodys. Also a very anoying features is that even though you can change options on the base station with a handset, .. 
Physical appearance: elegant