Buy it and you can test fire it all you want - I've never asked to shoot before I buy - do you ask the guy at the gun show can you shot it? And I've yet to see a gun store that lets you test shoot a gun for free - most do not have ranges.
TNT is a straight up guy, great to deal with, waited for me after hrs one time so I could get a pistol. I always look to see what he has when looking for a new gun.