...and it's 10 times better. It's also yellow/amber rather than green (works a lot better for me and I've read the color of your eyes can affect what you may prefer - I have blue eyes and a slight light sensitivity problem). Hence I do think there is a difference between the cheap ones.
Auto-darkening helmets (in my opinion) help you to 'aim' and control the start of the weld better (totally true). However I also have a gold lens by Weldability Sif (it's passive so no auto-darkening http://amzn.eu/d/8LNx2pH) and it's like seeing the weld in HD - you just have to alter your starting process so you have a steady aim and then nod your head to flick the visor down. There is also the fact that you can't alter the darkening from, say, shade 9-13 with a twist of a knob for different amps like you can on an auto-darkening one.
On the big plus side for passive lenses: I was welding once and for some random reason (I can't think why) the LCD flashed me - no harm, just color spots for a couple of minutes and a touch of a eye strain/headache later (the LCD even in grind mode blocks a lot of the harmful light spectrum). However I have never been flashed with the passive lens. So, if I can start the weld OK , I can safely sit behind the glass and concentrate and not worry about things like 'is the battery in the thing charged?'
If I had to have one...hmmm. Probably the Tacklife auto-darkening and periodically zap at it with a TV remote while wearing it to check it still works before starting to weld.