There is no count or limit foor the reviews. Any one can write reviews for any of the products listed. The more the reviews the better for the viewers isn't it?
If you are sure that your reviews are unique go ahead and post them. But be sure that you do not post specifications and description in the reviews.
If the product is already listed you can go straight for the reviews and post them.
There is a link below the posts to add reviews, you can click at the link and add your reviews.
What a review needs is your comments like
why you chose the particular product
your experience in using the product,
the reasons why you love or hate the product,
how long you have been using the product etc.
All the best and hoping to see more and more products reviews from you
India Review Channel