So is the new Xtar a better charger?
The spec says 350mA*4 or 750mA*2. In reality 750mA is only for one battery. It takes forever to charge just 2*18650 3100mAh. And basically wait to bore to charge 2*26650 5200mAh.
Tried charge one 26650 cell from 3.6v need around 4.5hours to get 4.18v and completed on 6 hours. Very long in CV mode.
Not quite so. First 2 slots on the left is one bank and the other 2 slots is another bank. If you put 2 batteries in the same bank, that is 1st and 2nd slots OR 3rd and 4th, it will charge each battery at 750mA. If you put 2 batteries one battery in each bank that is one in 1st, another in 3rd or 4th OR one in 2nd and another in 3th or 4th then they will be ballanced charged at 350mA each. I hope I am clear enough. If nothing works, you can always re-read the manual.
I tested again, apparently I was wrong. Mine, slot 1 & 4 is 1 channel. That’s why i saw only 350mA when charging 2*26650.
Do you notice the display become colorized when charging for long period and after the heat built up?
I do not have any 26650s. And my batteries have small capacities. So the charging does not last long. However once I put the charger on the carpet and realized it was getting hot so I had to prop it up to let it run cooler. I did not see any color change. You can turn tne back llight off so the discoloration would not be visible to you 
.How do you charge 26650s anyways? With jumper cables?
Later on I turn off the display. It back to normal once the charger cool enough.
Slot 1 & 4 can fit the 26650. In my case, I need to rotate the battery to find contact point between the positive pole in battery and charger. I use efest IMR purple, btw.
Ah! Yours must be a newer version. When it first came out, it was advertised as if it could charge 26650s. Even the box says so. But we got a charger with 18650 slots. Who says early bird gets the worm. Sometime it gets a bug. I guess the designers did not know the intensions of the producers huh.
Yours can’t fit 26650 at all at any slot?
Hmm.I can’t tell if it is due to newer batch or other reason. All i can say is that the authenticity code can’t be validated, LOL.