Back to on-the-go charging options. Just got this sweet wonder in the mail:
http://www.ebay.com/itm/371524811981 and done some testing.
It is definitely charging like a 30A/h capacity battery (took around 24 hours to top it with the 1.5A charger. However, the phone charging test demonstrated something within a 15Ah capacity so far (I plan to redo it in a more refined environment with the bare battery only tonight, as the phone was charging while online, and with periodic use). Still impressive, compared to what I'm carrying now. The urge to upgrade, besides the increased capacity, was also about standardizing on the micro USB plug, so I don't have to carry an adapter or additional cable, as well as adding more USB ports to charge multiple devices simultaneously.
Compared to many other similar offerings, my research suggests that this is the most slimmest cheap power bank on the market today, which is crucial for my "No Bag EDC" effort. It's very well made, curved corners are pocket friendly, does not produce much heat when charged or discharged, very lightweight, has 2 Amps charging and discharging circuit (important for faster than typical charging times), has over-current protection, has an integrated not a complete nonsense flashlight (two LEDs around 30 lumens total focused spot), cheap.
The solar panel on the side, though inefficient, still good to have (the a bit smaller one on my other similar powerbank was capable to prolong the life of the battery quite noticeably after being left behind the car's sunroof on the open parking lot for the entire day (got almost an additional full phone charge in 9 hours ~3 A/h).