Thanks @xtarflashlight for the pointer to this new test.
For those that can’t read German like me, here’s a link to a reasonably legible Google-translation: Review: XTAR 4150mWh
Good results in terms of capacity for the XTAR, but like @Mandrake50 once stated, my main doubts regarding those XTAR batteries are their self-discharge rates.
As he pointed out, XTAR claims 5%/month initially, and then 3% after it (internally) hits 3.6V voltage, but AFAIK no one has independently tested/verified that.
I would be very interested in hearing about such a test.