I bought a Xiaomi Mi 4i before 7 months. No doubts that its really a good mobile but it has some limitations. The snapdragon 615 processor inside Mi 4i lacks to serve a powerful performance. If anybody planning to buy a device in now a days then you should not consider this in any situation. Because it has been out dated and there are two many devices which can give better value for money.
You can consider Xiaomi Mi 4c instead of this which has similar value and form factor but has better specifications.