It’s no problem. 
The Defiant 1000-lumen 3D uses 3 D-cell batteries instead of Li-ions. As such it’s a little shorter but also heavier and fatter. Instead of having 3 XM-L emitters it uses XP-G emitters, so they put out less light for a given amount of current, but the light is still ANSI rated for 1000 lumens. It draws 4 amps, so it will murder any Alkaline cells you put in it, but if you can get good NiMH cells it will run for a couple hours, easily. Because it uses smaller emitters, and has a deeper reflector than the 3T6, it will throw much farther.
Technically the Defiant is not worth $30 as the finish, threading, and lens are all of inferior quality to the 3T6, but you are circumventing the issues with buying from China, and at least the lens is easily replaced with glass.