In general the Skype phone is awesome. We save a lot of money using our Skype phone. I'm not sure we needed to buy two additional handsets, but they're nice to have now that we do have them.
Well they phones work like 98-99% of the time. Sometimes, however the phones get de-registered and it has to do with the phone-router.
This last time was the worst set back we had. Eventually I figured out that the phone-router wasn't getting an IP address from the DHCP server on the wireless router. Basically I shut everything down that connects to the wireless router and then get the phone-router setup first. When the phone-router is working fine, it's easy to register all of the handsets. In fact, it's so easy that I forgot what the actual process was except for following the handset's directions. I didn't even need to do long resets on the phone-router.
I found some interesting information that led me to this solution from:
http://tinyurl.com/y8exmyz