I wouldn't shoot it either, a few rounds probably wouldn't make much difference (unless it wasn't even test fired at the factory) but why take the chance when you could rent or borrow a friend's 1911 to try out. Every shot does leave wear marks.
I have a like new 1941 Luger P08 that I'll never shoot, just too valuable. It's the only gun I own I won't shoot. Instead I shoot a mismatched parts 1913 P08.
The biggest issue with assembling an AR isn't so much getting the parts together right - it's getting the right parts together.
US Army 1966-69, VFW Life Member, Retired Geek