I am a user of a third-party uninstaller, currently using the latest beta version (4) of IObit Uninstaller.
- IObit Uninstaller 2 was natively portable.
- IObit Uninstaller 3+ are not portable and install silently into the Program Files, integrates into Control Panel, and File Explorer context menus as well an additional process run by the background service (LiveUpdate.exe).
(You can disable the service, and block Inbound/Outbound connections with Windows Firewall with Advanced Security, if you do not wish this to occur).
Despite this, I have found IObit Uninstaller to be very effective in removal of left-over files/registry items compared to other software. It's completely free, uninstalls 64-bit programs and in the latest Beta version it removes left over files from Windows 8 Store Apps.
There is no adware or toolbars bundled with IObit Uninstaller.