Thank's for answers.
In your case you can reduce costs by not buying Wise and simply using self-extracting archives. Installer should be more intellectual to prevent customer from misusing. Now I need to do many manual actions to prove that all other developers in our projects use the same version of TeeChart that I use. TeeChart it is only one from more than 10 3-rd party components that we use.
For this time I didn't see any reason of having two installers for VS2005 and 2008. Assemblies compiled for .NET 2.0 at VS2008, work fine in VS2005, but even in some cases then they not work well, you always can bundle installers with VS2005 and 2008 version in different folders.
You can leave separate installers for 2008 and 2005 but in this case they should create different entries in Uninstall menu(now they overwrite one another and I can't uninstall previous) and will be great if they will be installed to different subfolders by default.
At installer start you can simply add check is it key presented at:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\TeeChart for .NET v3
Modify DisplayVersion subkey to include for example build date, for example "TeeChart for .NET v3 Nov 3", and during installation you can warn user about already installed product and suggest uninstall previous or install to separate folder. In this case it is easier to me and others customers to make faster deployment and avoid from mistakes.
3. Installer executables. How I can differentiate them, for example September version from November. TeeChartNET3VSNET2005.exe and TeeChartNET3VSNET2008.exe didn't provide any file version numbers or any other tags.
Even in freeware Inno Setup I make better installers, with commercial tools (I guess you use Wise) this can be done with just several clicks, but user experience can significantly improve.
You can rename the installers to whatever you like when downloading the files.
This is error-prone solution.