Aliexpress - Rails

This post is going to be off da railz!
(This is the only pun you'll see in this post)

Below are various picatinny rails and related products for sale from the Evike, Airsplat, Airsoft Megastore, Amazon, and Aliexpress. Most of the time you can save money by buying directly from the manufacturers in China.
All prices listed here are the price at publication, they may change. There may also be minor differences between the products, but they're fundamentally the same. 

Offset Scope / Flashlight mount
Evike: $9.50 + shipping
Airsplat: (not found)
Airsoft Megastore: $9.99 + shipping
Amazon: $4.95
Aliexpress: $6.52

Barrel Rail Mount
Evike: $7.97 + shipping
Airsplat: $7.99 + shipping
Airsoft Megastore: (not found)
Amazon: $9.18
Aliexpress $5.99

30mm Scope rings (x2)
Evike: $12 + shipping
Airsplat: $9.99 + shipping
Airsoft Megastore: $4.95 + shipping
Amazon: $17.65
Aliexpress: $7.69

Dual Scope Ring Mount thing
Evike: $14.40 + shipping
Airsplat:(not found)
Airsoft Megastore: $9.07 + shipping
Amazon: $16.71
Aliexpress: $8.99

4 piece Plastic Rail set
Evike: $9.60 + shipping
Airsplat: (not found)
Airsoft Megastore: $8.95 + shipping
Amazon: (not found)
Aliexpress: $8.99

Tube Rail Mount
Evike: $20.00 + shipping
Airsplat: (not found)
Airsoft Megastore: (not found)
Amazon: $27.28
Aliexpress: $5.50

Generic AR RIS
Evike: $39.99 + shipping
Airsplat: $59.99 + shipping
Airsoft Megastore: $28.95 + shipping
Amazon: $26.65
Aliexpress: $25.88
Aliexpress bulk (50 pieces!): $783.99 ($15.68 each!)