I'm reviewing my home phone setup and am confused by a couple of alternatives, so thought I might try asking here.

Namely, what is the difference, in broad terms, between the VOIP DECT handsets like the Gigaset E630A or Yealink W60/W56 and an ATA with conventional cordless setups like Uniden and Panasonic DECT sets?

The backstory is that I've been on the latter setup for years now, using a worldxchange account with a Cisco SPA3102 which I wired into the existing jackpoints, so continuing to use our existing cordless systems.  They have changed a number of times as handsets fail so currently it is a Panasonic KX-TG7621 answerphone with 5 handsets linked to it.  We still get problems with calls dropping out after a while or sudden loud static so I've been wondering what the source of the issue is and whether alternative setups would help.

We like the simplicity of an answerphone basestation in the office with large buttons to set and clear the answerphone. Now with the dect system we no longer need phone jackpoints all round the house, so I could move the ATA into the office and connect it directly to the basestation. This would remove the house phone wiring from the system, but the symptoms don't suggest to me that is the primary cause.

It could be I need a newer ATA, or change service provider, or just replacement handsets again. I got to wondering about the relative build quality of domestic wireless handsets and SOHO targeted VOIP systems, but the differences aren't really clear to me.

It seems to me the Gigaset or Yealink systems combine the ATA with the basestation, and allow use of some VOIP features from the handset that we're unlikely to use much (vast majority of calls are local, with a very few national/international), but possibly the answerphone is a little harder to use. A second channel? on the same phone number would be nice on occasion, to answer/place a second call, but that would be pretty rare. Otherwise we're pretty happy with a basic caller ID/local answerphone system, we just want better reliability.

I look forward to any thoughts.