I've used the V1 and love it.
It was a back-up to my Nikon SB-5000 for a wedding last year.
I was so impressed testing it, I wound up using the V-1 for most of it.
I'll buy another one as soon as I can afford it.
I knew the V1 had a much longer battery life but it gave me more consistent good exposure than the SB-5000, which surprised me, being a Nikon Fan-Boy all these years.
The head also tilts back without having to rotate, which makes it great for bouncing the light.
And..it has a radio receiver to use remotely.
(The Nikon does too, but it's not as easy to use)With the dome head diffuser, it works great in a softbox or umbrella, filling them more evenly.
And....the V1 is about half the price of Nikon's current top of the line flash.
Re: round highlights...
The round head isn't that much bigger than a standard rectangular head so the difference of the reflection in the eyes may not even be seen.
For portraits, I'd use a modifier like a softbox anyway to smooth the shadows cast by the flash. Size matters! You need a bigger source to soften the light, not just have it be round. Used w/o a modifier, it goes give a smoother transition than say a TT860 or probably a lot of other rectangular flashes. See photo below. V1 on left, 860 on the right as 28mm setting.
Good video review
HERE.
I would buy mine from a local store if you still have one or
B&H,
Adorama (Flashpoint brand), or some other reputable brick and mortar store.