Interesting. I rarely bother to keep MSSQL loaded because it starts so quickly...
PS C:\> (Measure-Command { Start-Service MSSQLSERVER }).TotalMilliseconds
1127.5208
Alternatively, if you want SQL Server to start automatically without materially impacting startup performance, why not set its startup type to "Automatic (Delayed Start)"?As for shutdown, while it depends on how you're using it immediately beforehand, I've never seen it take more than a few seconds on a development box.
Primarily because I have SQL Server on it for development - the services have a extremely long shutdown and startup time, which doesn't need to happen for hibernation.