Edited to add: When your choice is between a Roadfood and Yelp recommendation - go with Roadfood.
I'm going to have to respectfully disagree with Holly on this one (but only partially)
Sometimes yelp recommendations outweigh roadfood recommendations and I'll explain why.
If you have a choice between a yelp recommendation and a Sterns
Reviewed recommendation on Roadfood
I would then go with the roadfood recommendation in heartbeat
However other than a few select posters on Roadfood whose advice I trust, I would sooner go with a yelp recommendation under the following circumstances:
1- Make sure that that the place has been reviewed several times
2- Make sure that the posters have reviewed at least a few places
3- If you've heard "good things" about a particular place and there are more negative reviews than you anticipated check to see the other reviews that particular person posted, they may just prefer a different style of restaurant...
Following these criteria to the letter I've found some excellent gems on yelp and also urbanspoon.com that I may not have found on Roadfood.