PanasonicKX-TGP600 SIP Dect Base Unit & Cordless Handset

I set up my KX-TGP600 late in the evening recently (3 KX-TPA60 handsets and 1 KX-TPA65 desk phone) with VoIP.ms.I'll start by saying that configuration of this phone system and its handsets will require some technology chops. Familiarity with VoIP concepts and terminology is a requirement, and it's probably NOT a good choice for those that think "Vonage Business" is an acceptable and cost-effective solution for business communications needs ;)One of the complaints I read here was that the requirement to enable the embedded web server from the handset was a stupid idea. Of course, the security-minded among us will understand the reason for this feature: you rarely use the web interface, so why leave a potential point of vulnerability permanently available? And if you're NOT going to leave it permanently available (in keeping with good security practices), how exactly would you disable/enable it using a base unit whose only user interface is a single button? Answer: via the handset.Forging ahead... Configuration was actually relatively straightforward; I did not need the administration manual at all. I updated the firmware (wow that took a while), and set up 2 new subaccounts on VoIP.ms (my VoIP provider) for work and personal calls from/to it.The only issue I had with initial setup was that I could not get the phone to register against the subaccounts I'd created unless I used the subaccount name for the "Phone Number" in the SIP settings. This is in agreement with VoIP.ms' instructions for the KX-TGP500, but the problem is that the callerID displayed to the outbound call recipient becomes some portion (in my case, the 2nd through the 6th characters) of the subaccount username. To fix that, you need to set a callerID number in the VoIP.ms subaccount configuration that overrides it.There's also a minor mechanical/design problem (that admittedly will affect very few people) with the KX-TPA65; I use a Plantronics DECT headset (CS361N), which I absolutely love for extended calls. Unfortunately, the TPA65's handset is so top-heavy that the imbalance it creates will cause the Plantronics handset lifter to either completely eject it from the cradle at the middle or high lift settings, or fail to to release the hookswitch at the low setting about half the time.I've worked around the issue by sticking a small amount of some tacky rubber compound at the bottom of the mouthpiece well. This allows the top end of the handset to swing up and disengage from the hookswitch while keeping the bottom firmly in the well.Sound quality is excellent in both directions, and the configuration options for ringers, line availability, button customization and directory management are very useful. It's much more configurable than the Gigaset C610A-IP have out at our vacation home. It's still very early, but I'm quite pleased so far.Update:One thing I was unable to test when I set it up that evening was the receipt of inbound calls (didn't want to wake up the missus). And, unfortunately, they weren't working when I tested the following morning.I checked for differences in configuration between the Panasonic and my venerable PAP2T-NA, and discovered that both registration expiration and Enable 100rel (RFC 3262) differed. One of them fixed the issue (at least for now), but at this point I'm not sure which. I set registration expiration at 180 and 100rel to disabled.Also, voice mail notification via the display wasn't working either, but I believe setting "Send SUBSCRIBE to Voice Mail Server" to Yes resolved that... at least, it's working now.

Purchased multiple units from Amazon and I would not recommend this phone based off of several issues. The units are installed on a perfectly configured company SIP-based PBX. The issues described below are not due to misconfiguration they are due to Panasonic selling an inferior product.1. The audio quality is terrible. The handset's internal speaker is just too small. The sound is very tinny. If you are familiar with G.722 wideband clarity you will be disappointed in this phone. If you use Polycom SIP phones you will be even more disappointed in how these units sound.2. The firmware is terrible. The latest firmware as of 4/2016 (and prior) is unstable in several areas, such as networking, and will cause stability headaches. SRTP just makes the stability issues worse. I have to run SRTP due to our corporate policy. So, to make this phone a LOT more reliable, I have had to use the Canadian firmware on this US model. I shouldn't have to do that as it is a bad idea.I have cheap analog DECT cordless phones off an Adtran unit that sound better than the TGP600 with the TPA60 handsets. They cost about $10. What a shame.

Works quite well. Love the wireless desk phone that you can get with this system as it allows you to have your desk anywhere and not confined to a specific location or wall.Only negatives: screens are a bit small and the rugged handsets are quite expensive.

Simple setup, good sound quality. Battery life could be better, I’m rarely more than 10 feet from the SIP station so I don’t really understand that, but overall good value.

I've ordered 5 of these only to discover the firmware will not support a blind transfer. Just spent 4 hours diagnosing the issue with my carrier to no avail. The problem is confirmed on 3 different handsets from Amazon in three different shipments from different suppliers.The failure pattern of 3 for 3 from different Amazon suppliers suggests incomplete testing before product release by Panasonic. I guess it's okay to get one of these if you don't plan to do blind transfers - but the handset is below usability standard for any business.

Be prepared for A - LOT - OF - WORK.The bad:First - these don't work out of the box with Vonage Business. There are workarounds, and they do work, but MAN. Whoever designed the web interface and more importantly the management doctrine for this handset must have been insane or stupid.First of off, you need to enable the web access for the base station ON THE HANDSET! WTF? Is this to prevent all those cordless VOIP phone hackers I haven't' heard anything about ever?After that you can connect to the webpage. Don't even TRY to use a standard browser. So far it only worked on google chrome AND ONLY in incognito mode because for whatever reason, the page caches your responses and resubmits them everytime the page loads instead of only when you hit the save button.This has SERIOUSLY failed website 101.The wallpaper function is not documented at all (to change the handset wallpaper to a logo) and so therefore doesn't work. No resolution or file type requirements, and no one has a solution via rapid fire google searches.There are SO MANY FUNCTIONS on this phone that are annoying, poorly designed, or just straight up broken. And the latest firmware updates do nothing to resolve this.The good:They have good range, and some of the options are extremely high level power-user type stuff if you have the need for those.If you want basic, easy to use. I recommend steering clear of panasonic.