LinqConnect and ORMBattle.NET
ORMBattle.NET is an open-source project for ORM comparison, supported by a development team from X-tensive.com. This project contains a set of tests for feature-oriented comparison, but it is more focused on the performance tests (CRUD operation performance, object materialization, etc.).
LinqConnect development team agrees with most of the tests. The results on the whole are reliable enough to consider them when choosing ORM framework.
We already are studying the situations where LinqConnect showed bad results and working on performance improvement.