More and more people are starting to buy chineese phones for the reasonable prices. Considering this, I suspect that prices will start to get up pretty soon. So, if you really love MIUI I recommend you to buy any Xiaomi phone you can afford. Mi3 is an awesome phone and if you can wait like 2-3 more months and get more cash you will buy something even more nice with all these octacores coming :)
1st you need to find if there are any CWM and ROMs for it. Then, when you find them, I'm sure you will get the instructions to flash it. But in general, for MTK chipset SP Flash Tool is used to write phone partitions ;)
In december I've bought from a known international China seller Jiayu G5 Advanced phone. Full phone specs found here: http://www.jiayu-store.com/jiayu-g5-quad-core-mtk6589-4-5-inch-ogs-ips-screen-smart-phone-ram-2gb-dual-camera-32gb.html.
All I can say about this phone is that I love it. Materials used are awesome, the whole construction of the phone itself is very good and daily use is above expectation. Camera sensor is one of the top at the moment but the low quality of flash makes it almost impossible to use in dark conditions. It has an unofficial MIUI port but all working for daily basis. I don't feel sorry for the 395$ payed including DHL shipment, custom tax and the extra 3000mAh battery. The screenshot posted is from phone used with his stock 2000mAh battery with 2 SIM active.
In the /mnt directory I only see:
so I guess only theese are mounted
in teh storage directory I see
sdcard1 <- this should be the external SD but it shows empty when I access it
I guess there is a conflict with the mounting points from stock JB kernel (this mounts them in /storage/sdcard0,sdcard1) and the CM kernel wich mounts them (if I remember correct - to /mnt/sdcard,external_sd)
pretty darn hard because I can`t really provide a logcat yet...I try again and post it here if I can ;)
PS logcat here http://db.tt/zQt8iz3M and here http://db.tt/mCmb8ADN