The main improvement of VisualSVN 5.0 is the full support for Visual Studio 2015.
Upgrade to VisualSVN 5.0 is recommended for all existing VisualSVN users. Note that upgrade purchase is required for commercial VisualSVN licenses issued before June 3rd, 2014.
See the changelog for the complete list of changes.
Support for Visual Studio 2015
The main improvement of VisualSVN 5.0 is the full support for Visual Studio 2015. All VisualSVN features are now fully compatible with the newest Visual Studio release, including support for the new Universal Windows app projects, cross-platform mobile development and other enhancements. For further details please consider the Visual Studio 2015 Release Notes.
Upgrading from VisualSVN 4.x and older versions
VisualSVN 4.x licenses issued on or after June 3rd, 2014 are eligible for a free upgrade to VisualSVN 5.0. Commercial licenses issued before June 3rd, 2014 require an upgrade purchase for VisualSVN 5.0. The current upgrade price is $49 for the Professional License and $1950 for the Site License. The upgrade is free if you are using VisualSVN under the Community License.
You can download the latest VisualSVN 5.0 build at the official download page.
Also, you can purchase upgrade to VisualSVN 5.0 using the online purchase form.