I'm looking for a software/service ranking solution – would marketpress be ideal?

I’d like to add functionality to my site that would allow our members (only) to review a list of vendors or services by category or tags that can be sorted by a number of options like ranking, date, etc.

The users would ideally be able to rate each of the vendors with a simple 4 or 5 star system while also having the option to add their own comments/review.

I’m having a hard time finding something like this but it would seem that some ecommerce solutions are very close to what I need – except that I don’t want any of the purchase or checkout options.

I may be barking up the wrong tree with ecommerce so please feel free to recommend any other type of plugin or solution. I was considering stripped down forums with a ranking system but everything I’ve seen so far has just been to hard or risky to piece together.

Any suggestions are appreciated!