Have you used a sheriff/constable to serve papers/citations for lawsuits in Houston? How was the processing time?

Title says all. In the process for suing an electric company in small claims. I am researching the need to have the citation served, and process servers are telling me if I go with the sheriff/constable's office I'm going to wait ages. Curious what people's experiences have been, but understand that past experience doesn't guarantee future performance. Thank you in advance!