When we patch our vm hosts, and tool updates are available I will update the tools on the guests using the advanced options
/S /v"/qn REBOOT=R" to suppress the reboot. Then the guests will be rebooted when they get Microsoft patches. The delay for rebooting this particular guest was 18 days. I have been doing patching this way for several years and have not had any issues. This was on a Windows 2008 R2 server.
Has anyone seen any issues when delaying reboots from tool upgrades?