If you fly more then 1-2 times per year it is certainly worth it. You just never know how long the regular security screening lines might be. Screening is faster, you don't have to take off your shoes or coat, etc. partly due to the fact you are considered less of a risk since you had to go through the TSA pre-check process to get approved. My experience has also been that those who travel frequently tend to have pre-check and are more familiar with the screening routine. Therefore, you are less likely to get someone in front of you who has NO idea what they are supposed to do for security screening, what is allowed/isn't, etc. making the line move VERY slowly. Some very small airports may not have a separate pre-check line usually due to a small volume of travelers, but all of the major airports usually do.