Reviews are a natural extension of my JomSocial community. I tried the others, but I have found no other product as capable as Jreviews.
You can actually build applications that are not strictly review apps with Jreviews, but its focus is reviews. I have video and other website reviews on my site and directory of resources (without the reviews).
Out of the box you can create decent review apps without a huge learning curve. To create totally custom displays does require some learning, but one would expect that with such a capable product.