We are excited to announce FREE T4 Editor with Intelli-Sense for all namespaces and MVC Host used in standard MS MVC 1.0 RTM Templates. In addition V1.4 added .t4 extension support for GAT/GAX users as well as an other number of performance improvements for large projects using #include statements.
Here are the screenshots of the FREE edition editing MVC T4 Templates with Intelli-Sense for those namespaces and the MVC Host build-in.
Here is the download of the tangible T4 Editor
Learn here how to customize T4 Templates for MVC.