Advantages: zero effort Disadvantages: require experienced users, slows user producitivity, updating controls is not intuitive Visual Studio 2005 SDK contained a VSPackage called Toolbox Control Installer.
This increases chance they will actually purchase your product.
Please note that VSI and VSIX package installers contain features like displaying EULA, choosing which components to install or localization.
When deploying your controls for use in Visual Studio, you won't need an installer on top of the package.
On the other hand, there is a group of users who are not experienced developers, but are in charge of trying some products in a given company (e.g. These people can install the component, play with it and they would really appreciate if it just works.
The project is outdated since it does not support Visual Studio 2010 and newer.
There was a trouble with VSPackages in providing a Package Load Key (PLK) which can be generated only manually using web form.
The requirement for PLK vanished with Visual Studio 2010 (hooray! The nice thing about VSPackage approcach is that it does not slow down the installation process.
Advantages: does not require updating registry or GAC, full control over Toolbox Disadvantages: very slow, separate installation required for every version of Visual Studio A VSPackage seems to be a natural option.
VSPackages allow any type of Visual Studio extension and you can manipulate Toolbox as well.