Depends on how old. Up to 40 years old still requires annual inspections. More than 40 requires an inspection every 2 years. And the inspection month is April, not your birthday month. Older than 1949 does not require inspections.
PART Saf-C 3224 ANTIQUE VEHICLES
http://www.gencourt.state.nh.us/rule...saf-c3200.html
Other than that...there's no practical benefit.