Is buying from Aliexpress advisable?

Hello everyone.

Currently I'm using a Huawei Y300, which, as you may know, is too outdated to keep using these days due to having only 512mb of ram, Android 4.1.1 Jelly Bean and a measly dual core S4 Play. Some months ago, I had an Xperia Z1 that I bought used from a friend at a fairly low price, and I just had to repair it because the screen was broken. So I did, and I used it for some months before it broke down. Now, I have to replace the screen, the camera (It has become awful, I've cleaned it and the Huawei has better results), the back cover (it's cracked too) and the frame, which is slightly bended. Buying all of those parts is almost as much as buying a new phone.

So that brings me to my question. I plan on buying a Mi4c from Aliexpress, and the seller has them (including one pu case) at 125 dollars. The seller is called Hong Kong Goldway. Many people post five or four star reviews for it, and they feel satisfied. Is there any risk in buying it? Are there better phones for the price?

Many thanks for your help.