Battery was replaced in January. It was fine for a month, but its now worse than it was before.
They have had at least two rounds of issues with bad batteries from their supplier. It is unfortunate. I have 2 Terics and they have both had their batteries replaced 2 times (each). But, now they are solid. When sitting turned off, they seem to drain *roughly* 10% per month.
The good thing (to me, anyway) is that I have never missed a dive because of a battery issue. When I've had issues, the battery has been draining faster than it should when stored, but it still lasts PLENTY long enough to get through 3 or 4 days of diving. The issue has only meant (to me) that I needed to remember to put it on the charger a day (or a few days) before going diving - IF it has been sitting for a while. Now that my batteries are fixed, I expect I could charge them, let them sit for a month, do a week of diving on a liveaboard and not have to charge my Teric the whole time.
And, when I've sent mine in for battery replacement, I send it Priority Mail (2 days to get there), they turn it around in 1 to (at most) 2 days, and send it back the same way. So, 1 week total from sending it off to getting it back.
As for use as a daily wear, I tried that when I first got my first one (soon after they originally came out). I was getting right around 50 hours. That was as good or better than the Moto 360 smart watch I had previously. Now, the newest firmware (released today) has added some power management options. I suspect you could set the Teric up to get much more, if you wanted.
Personally, I tried it, just to see. But, I don't normally wear a watch at all. And when I do, I want something very thin and light. So, the Teric is not my choice for a daily wear watch - unless I was on a dive trip and felt the need to wear a watch for some reason. Then it would totally be fine.
Also, just for the record, when you put the Teric in Watch mode, all the dive stuff IS turned off. You don't need to turn off AI or anything like that. If it's in Watch mode, the AI IS off.