I think this is a must-have for the value.
It does NOT have High Speed Sync - which was a disappointment, but I've found it to still be a 5 star value.
What I love most about this is the exposures - the power seems to be consistent and it works well with a diffuser.
Exposures seem to always be accurate without needing compensation! wow
I love using this for a bounce - others I've found just don't have quite the consistency I've come to love and rely on from this one.

The zoom range is from 18-180, but I don't think it is actually as wide as 18 and the 180 might be slightly overstated also.

In my humble opinion, this is simply a reliable workhorse of a speedlite that nobody should overlook at this price!

3/22/18...Update. Finally got to use my replacement flash at our annual woodcarving show. Impressed! In the "bad old days", B.D. (Before Digital) We were always warned to "form" our main flash capacitors by firing them manually 3 or 4 times, to "wake them up". The first exposures I took were underexposed, but a +3 compensation on the flash cured that. As I took more photos, exposure compensation dropped from 3, to 2, past 1, and finally leveled out at 0. My Nikon flash doesn't need that sort of "warm up", but, at 5X the price, you'd expect it no to. A GOOD, basic flash, with a good set of features that work! Some photos I took once the flash was warmed up.
I really liked this flash, It worked well, until it didn't.
Great features! Reasonable guide number, fairly light, modes, a delight to use, bright LCD display, easy adjustment, the head depresses -7 degrees for macro, and thermal protection, to keep us speedlite commandos ("Strobists"?) from burning it out prematurely! It comes with a nice stand, too.
The flash is a Christmas Present from my daughter, and I really, really wanted to like it! When I first hooked it up to my camera, I loved the metal hot shoe, but after a few exposures, I noticed the color balance was not ~5600 Kelvin for daylight or flash, but more down the range to ~2700 K, which is Tungsten light. It also started underexposing by 2 stops or more, and exposure compensation didn't help.
Just hoping I had gotten a flash that was built on a Monday or Friday, I returned the defective unit, (Thank You, Amazon!) and ordered a replacement.

It came this morning, and the Postman hadn't reached the end of our Cul de sac, when I had a fresh set of Eneloop batteries in it, and started testing. Good results!, Proper exposure from semi-macro to living room distances. In the midst of all this , my camera's LCD screen went blank! 'Oshoot!" (or words to that effect, sez I. Also "DRAT!" User error! I found that I had accidentally changed my shutter speed to 1/500 sec, which was over the flash's sync speed of 1/320 sec.

Farble corrected, the flash performed flawlessly! Then...WHY only 4 stars? Longevity and reliability have not yet been tested. I don't expect that for the price, the build quality will match that of Nikon or Canon's flashes, but for the majority of us, I suspect it will do just fine. If that proves to be true, I will upgrade.

It is a flash and allows for a bit more versatility than my Bower which is on its death bed but still usable. I use them off camera so not worried about the TTL nor have I tried it. The zoom sounds horrible like there is something in the screw or just needs some lithium. I have not had the chance to take this apart. Does the trick for the price so that outweighs the negatives. I can mount it, gel it, stop it down, and fire it. If you are looking for a cheap flash that has a sold feel to it, this is your ticket. Perfect for OCF, backup, or main, if you need. Does have an optical slave and can be linked to a command, if I am not mistaken. I personally use a different wireless flash trigger connected to the hotshoe for my needs.

I've only had the VK750-II for a few days and have done nothing but try and gain some familiarity with the flash. But made one discovery that may help other people who've discovered the same.

One thing that I struggled with, and I've seen various questions online about, is with the Zoom feature. Typically, you would press the Zoom button and use the D-pad to change the zoom level. I noticed that this feature appeared to work intermittently, and struggled to determine why. As other reviews have mentioned, the manual is pretty bad and was no help at all in figuring this out. What I've discovered is that the there is an internal switch that is triggered when you pull the Diffuser out. This switch seems to set Zoom to 14%, you lose the ability to control Zoom, and Zoom does not adjust as you change the lens zoom level. Once you slide the Diffuser back into the flash body, manual control of Zoom is restored and again automatically adjusts when you change the camera's Zoom level.

I hope this helps to answer the question for others who've been unable to figure this out.

This flash is EXACTLY what you want if you are only an occasional flash user, but want something that produces better results than the pop of flash on your Nikon DSLR, and you do not choose to tie up several hundred dollars in the admittedly excellent Nikon Speedlights. I ordered my first one with the idea of sending it as a gift to my friend who is a budding photographer and who gets my old Nikon gear when I upgrade from time to time. It arrived today, and I decided to test it out.

I opened up the box and did not even consult the manual. I popped in some fresh batteries and put it on a D7000 I had laying around. I just switched left it as it came out of the box, which is defaulted to TTL. I then took a series of shots with direct flash, and bounce flash. Direct flash looks good, bounce flash looks great. The unit zooms automatically and is accurate, but do remember if it is not zooming to wake up your Nikon if it has been a bit between shots. I repeated the same shots with my Nikon SB-600 and my Nikon SB-800 and they were identical in results to this flash. I then, without ever opening the manual, was easily able to set up remote TTL flash. I just set my D7000 in Commander Mode, set the Neewer flash to S2 mode and was able to fire it off camera with great results, again indistinguishable from my Nikon Speedlights.

This unit is clearly a knock-off of the SB-800 and a very good one, Construction quality is not quite as good, and this unit may not last quite as long, but given that a used SB-800 is $300 and this one is $52 brand new, you'd have to break six of these before you lost money on the deal. As much s I love my Nikon gear, unless you are using your Speedlight daily, just buy one. If you want to play with more than one light, these make great spares. I was so impressed that since this is a gift, I just ordered two more for myself!