I would only do that on occasion where I need to maximize my connection speed and multi-task between my laptop (connected to the pocket WiFi), the tablet and the smartphone.
The battery comes with a back cover for the handset to fit the new form factor.
Last time I remembered using this was during Computex in Taiwan and Samsung Unpack in London where I had to tweet and live-blog at the same time (I was using two different 3G providers).
Anyway, the 5000mAh Li-ion battery is exactly twice the capacity of the original one on the Galaxy Note so more or less you get around double the battery life.
I’ve tried this on many occasions but the graph above shows the battery life over a span of 48 hours where 3G is active. The first 24 hours was dedicated to just mobile browsing, Twitter, FB and a few other stuff.
On the second day, I activated the WiFi hotspot of the Galaxy Note and connected my laptop to it for web surfing and blogging. That’s when the battery started to get some serious stress.
In any case, I managed 44 hours with 14% battery life left. The battery was totally deleted at around 48 hours. Not bad for heavy usage.
The 5000mAh extended battery is being sold by Hot Gadgets over at Sulit for only Php2,180 and comes with a custom back cover (see listing here). They have a similar one, though only 3500mAh, for the Galaxy S2.