Reliability issues are possible with either gun, but both makers have excellent customer service departments that have a proven track record of effectively dealing with problems. There are hordes of satisfied owners of both of these guns out there.
Accuracy on either gun is as good as the shooter. The long trigger pull on the LC9 affects accuracy for a lot of people, myself included. For that reason, I far and away prefer the Glock-like trigger on the Shield.
Good luck finding one though.
JOIN THE NRA!