I have ordered more than 350 times on Aliexpress. Ranging from 1 dollar stickers to 450 dollars ECU Flashing tool. I have used un-registered shipping for cheap parcels that costed less than 10 dollars and anything above that would be either by China post registered mail or Singapore registered mail. Anything above 100 bucks i always use DPEX which cost 15 dollars onward depending on the weight, totally trackable and delivery with in in 10 days.
I have experienced fraud from sellers as well where they would send a totally different item so i aliexpress refund me fully, then some times i got damaged product where i was sure the damage was done in transit so i asked for partial refund. Then there were some orders where shipping was cancelled and i had to ask for a refund.
Once i bough a 150 dollar item and it didn't worked with my bike so i had to send it back to seller via Pakistan post and when it was delivered then i got the refund.
I have stopped using un-registered parcels because you end up getting nothing and waste more time than the cost of the parcel. Registered parcels always come on time as well, in my case 2 to 3 weeks max.
So i advise every one to spend some bucks and save your self from bad situation where you had to dispute.