The last thing you should look at is the over all visual impression you get from the work. If you have taken a good look at your farrier's work and are still uncertain of the quality, there might be some validity in getting a second opinion. Doctors and vets are frequently asked for second opinions. Expect to pay for it. Don't be surprised of you get turned down though.
Many farriers are reluctant to evaluate the work of other farriers in their area.
If you do get another farrier to evaluate your farrier's work, keep the results to yourself. Spreading negative information around the horse community is like shooting yourself in the foot. It will come back to haunt you. You will get a reputation as a gossip and a trouble maker and find it difficult to get along. Farriers, vets, trainers, etc.