I’m just going to say that the only reason to use an ATA these days is for fax, and the best ATA for fax is made by Netgen. The others cannot use their patent. Using a Netgen, most faxes go through the first time at a decent baud rate. Now on to the phone.
Get a sip phone. I made the transition in 2013 and wondered why I hadn’t done it before. Yes, people on the other site were suggesting it in 2009 to me, it’s 2025 for crying out loud. I have also never had DTMA talk off with a SIP phone. Get a SIP phone and use CallCentric unless running your own SIP server like I do. Don’t forget to use a SIP client on your cellphone. I run my own SIP server, and I was in Saigon in 2019. T-Mobile had free text and data while roaming, but non-WiFi cell calls were 25 cents per minute. I used my SIP client and my home phone number while riding in a taxi in Saigon, calling my bank in a moving vehicle over cellular data without a hiccup. I never noticed any real lag.
Yep, I’m being preachy, but one of the first things I noticed when switching to a DECT SIP phone base with 5 handsets is that while on a call, if an incoming call came in, it would ring the other handsets, and all 5 handsets can be on separate calls simultaneously. There are more treasures than I have mentioned. The only way I would use Ooma is with the Telo and Telo handsets, not by plugging an ATA into the RJ11 port unless it is for FAX.