And if S4 is really making use of the 8 cores inside (non-US models), you better have a big battery otherwise that 2600 mAh S4 will run out of juice before the 2500 mAh Oppo Find 5.

FORBES: First Impressions of Samsung Galaxy S4

Not sure how this slipped under our radar, but recently Oppo Mobile CEO Chen Mingyong teased that his upcoming flagship phone, the Find 5, will again feature a non-removable but "certainly big enough" battery (for the sake of anti-counterfeiting and, consequently, safety) as well as a 1080p, 441ppi display.

ENGADGET: Oppo CEO says quad-core Find 5 will feature a 1080p, 441ppi display, forgets to wink at HTC