Why you shouldn't buy Xiaomi products?

If you are anything more than a “casual” android user, you do understand how critical is it to get new android versions on your phones, reasons ranging from new interesting features, to security to better battery life.
Xiaomi tends to ship its products with MIUI, their own operating system built on top of Android. It has a clean material design UI, but full of shit. Adds a lot of MI alternatives(read bloatware) for the google apps, wait I don’t even live in China, and also laggy and highly unresponsive.
And that’s the reason why you shouldn’t buy it? In short yes, continue reading for the reasons. Xiaomi is highly understaffed on the development side(makes sense, helps them make more money). Very few developers working on a wide range of products that it owns, leading to (terribly) slow updates. I was proud for having bought one of the budget best tablets in the market(hardware wise), but not anymore, it’s stuck on KitKat, and probably is going to be there forever.
Xiaomi’s dev team claim to be releasing updates after updates, but guess what? They are updates of MIUI trying to fix some bugs that they introduced into the system, slow claps. Had they just ported stock android, these bugs would never have existed.
I know what the geeks out there are thinking, wait, why don’t you just flash a custom ROM? If you don’t know what a custom ROM is, it’s simply some OS built for your phone by someone else(and not the official one). It can a lot of times be much better than your stock ROMs(official OS), yes Samsung owners, you know what you need to do now. The answer to this question is, there isn’t a fully working custom ROM available. Why? Because Xiaomi is full of shit. Why are you blaming the company for independent people creating ROMs? Xiaomi has a history of not releasing the kernel sources for a lot of its devices, or releasing it after a delay of a year or two. Sources
Without kernel sources, it becomes nearly impossible for someone to port a ROM for a device. They need to know completely about the hardware for writing the sources.
I know what you are going to ask next, why should they release it at all? They wrote the code, their wish to do it if they want to, right? No. Since MIUI is built on top of Android Linux kernel, it needs to comply with GPL, which clearly states that, the source needs to be released with the distribution. Read more about it here.
Did nobody notice this violation before? They did, a lot of people have been requesting Xiaomi to release their sources, but they have been turning a blind eye to them. I would suggest anyone who uses their android device for anything more than taking selfies to not consider buying Xiaomi.