I just found this blog post describing the experiences of one Querydsl HQL user : JPA 2 Criteria
The blog post mentions the following benefits of Querydsl in comparison to JPA 2 Criteria :
* conciseness and readability (also discussed here)
* extendability of Query classes (also discussed here)
* support for other backends (JDO, SQL, Lucene etc)
Here are some other Querydsl user comments
"...We have applied Querydsl to the articial playground project and to a realworld application, LeanCast. Querydsl has been easy to get running, and easy to write compact and readable queries in. Integration in an existing project has been as painless as it could be, and we have had almost no problems."
"...Where we had problems, they were resolved in manner of hours by the Querydsl developers, which both seem dedicated and got a company backing the development. The API is complete, making all queries we have tried to express possible. When we had a request for a simplifying addition to the API, it was willingly accepted. ..."
Stein Magnus Jodal
"...Querydsl rocks! It's the best thing since sliced bread for data access in Java."
"...Using querydsl you keep the reference to your HibernateQuery object and you can apply as many joins, wheres etc as you can, in any order, so that you can get a totally mutable hql query without ugly string concatenation. "
We at Mysema hope that you like Querydsl as much as we do ;)