There has been a lot of debate about why LG used the Snapdragon 801 instead of the 805 and initial test prove only a marginal difference for power users, especially the SOC. The GPU on the other hand is more futureproof.
What I want to know is why LG went with last years Sony IMX135 camera sensor instead of the new IMX214 that the OPPO Find 7 and Oneplus One use? Sure we have OIS and laser focus but the improvements the 214 bring are significant enough that average people will notice. Like Reatime HDR in video and less colour crosstalk and the fact that it is slimmer. How much more expensive would it have been to put them in considering that the OF7 and OPO are older devices?
Here is an article about the Mi4 and its sensor http://www.doi-toshin.com/xiaomi-mi4...just-stunning/