Summary: I worked on a VOIP installation using these phones which were selected due to Cicso's reputation for quality. The issue with this phone is if you use this phone as a receptionist phone you will quickly find out it has a serious design defect. When a caller (Call A) calls the business reception picks up. Reception then proceeds to make a transfer by pressing the "x-fer" soft button and the extension.
Summary: I purchased this exact phone over a year ago brand new from our VOIP phone company, who told us that it was better to buy from them, because the phones come with the correct software already loaded. Well when I had to set up a new office and add phones, I decided to purchase a reconditioned/used phone and try to configure it myself. Well, the phone looks brand new, and configuring my software took all of 5 minutes with instructions from my VOIP provider.
Summary: I purchased this phone thinking I would save a little money but ended up paying more than if I would have went through my VoIP provider. I had to purchase a separate power cord which was $14.00. I think they should tell you in the description it does not include a power cord.
Summary: It's an IP phone, what'dya expect? :-) JK.. we have a number of the Linksys version of this phone deployed and needed to add a couple more. They made some changes for the better. The receiver feels quite nice and there are some additional buttons on the menu that aid in use. I definitely recommend it.
Summary: The Cisco SPA 504G is a great phone to use. The call clarity and speakerphone quality are very good. Most people who get one are going to use it with a service provider that can automatically provision the phones but in case you try to do it manually, that can be a pretty complex process. Fortunately, most users will never see that.
Summary: The sound quality on this device is very clear (on the handset and speakerphone). It is noticeably better than my Panasonic cordless phone (connected to an ATA device). The people at the other end of the line also say the sound quality is better. It is also very ergonomic and easy to use.