Is that right? I didn't know the other 1300's are an inch longer. That's an awfully cumbersome pv! You also have to take into account the extra 1/4 inch or so for the 510 threads on the ego style batts. It's really an inefficient design that I imagine was a workaround to make it 510 compatible, and the reason the echo-e carto holds less liquid than the echo even though it's the same size.
I've been using my echo 1300 for about 5 days now and the batts have lasted me between 17:40 and 22 hrs. until they blink out. Which is plenty long for me. I have gone to using one per day and charging the other overnight and not fully discharging them. When fully discharged they charge in about 10 hrs. for me. I originally let them run till they blinked just to get an idea of how long they would last me. This spanned more than a day per battery and I had to record when I stopped vaping at night and when I started vaping in the morning just so I could time them.
From subjective experience it seems to me that the current from the echo is stronger than an ego on the echo-e, but weaker than the Riva on the echo-e. I'm thinking it might effectively be running somewhere around 3.6v. I don't have the equipment to test if that's the case, though.
I have the chrome too, and I agree it's a great looking pv. The batt lasts me a full day and I top off the carto either before bed or first thing in the morning and then again in the middle of the day and that's it for normal daily maintenance. This is by far, the easiest pv to take care of that I've ever had. And while the vapor performance and flavor isn't quite as good as my Riva on an echo-e, it is more than adequate for me and the other advantages I've already explained outweigh these minimal disadvantages. Others may prefer the extra maintenance to get the slight performance boost, but I'm enjoying not having to fiddle with my pv to keep it running.