trust your LBS?
I am always a bit paranoid about riding a just assembled bike without thoroughly inspecting it first so I have never riden home from a LBS on a new bike even though I ride everywhere else. Today I become way more paranoid as I brought a new fixie home to replace the one I just sold and was testing the seat height and doing trackstands in the kitchen when I felt the cog tighten as I put forward pressure on the pedals. Well, I was rather upset as I figured the the least the LBS could have is properly tightened the cog and lockring. I got out my chain whip and lockring tool and took the rear wheel off only to be horrified to find the lockring was so loose I was able to twist it right off with my fingers. If I had ridden it I could have severly stripped the hub. I know one LBS where I am never spending another dollar.