We had a VSB opener for a couple of years, and it worked very well.
Once you have the sensitivity adjusted correctly, there's no problem with locking the chooks out if it's darker than usual because the birds are light sensitive too, so just put themselves to bed earlier!
However, ours burnt out the motor after just over a year, and VSB to their credit sent a new unit out. In hindsight, I believe this may have been our fault due to the door freezing in the shut position overnight.
We had the remote sensor version, mounted inside the house, and I definitely think this is a good idea for longevity.
Unfortunately the roof our our henhouse developed a really bad leak last winter, which filled the electronic box up and broke it (my fault). We haven't bothered replacing it, firstly because they're damned expensive, and secondly because we now have geese and ducks to put away as well, which defeats the object.
However, if you can put a porch around the door to protect from freezing, and protect the unit from water ingress, and I would definitely recommend the VSB
.