In Windows 7(i.e. MSI 5.0), there is a property called MSIFASTINSTALL which will improve the performance of your installer. Or else, you can turn off the rollback option by setting property DISABLEROLLBACK. This property is available in earlier version of MSI 5.0 too.
Please share your knowledge to improve the install experience. Also, I cannot find the right way to improve the performance of Uninstall. We use huge set of files/folders (more than 70,000) and components like 35000. It hangs in the file costing process and do not know how to avoid this delay. Sometime it hangs for more than 2 or 3 hours to uninstall in XP or Vista machines
Edit: I did some hack in my install by zipping the folders which has huge file sets and reduced the components size like Christopher said. It improved the performance drastically. yes ofcourse, I lost the MSI installer pattern by doing this concept and it is not recommended approach. However, it is trade off when we want to achieve this and our user really do not want to have file version details when we uninstall/upgrade the patches.