You may need to travel a little bit to find a good quality machine shop and builder... One in your neighborhood may not do as good of a job... Quality is worth a little travel time.... Otherwise you get what you pay for or won't travel for....
There is a parts store with a machine shop close to me, but back in the 90's they did a valve job on a set of heads for me and those heads dropped a valve within 10,000 miles... I now use a guy in Dearborn Heights, Michigan who does great work and I have ran his heads for hundreds of thousands of miles on one valve job... It's worth it for me to go to Detroit for him to do my work as I know he does good work and I can trust him... He's done many sets of heads for me and they have all held together...
It's your car, your choice... Convenience in this case may not be the best option... I would go with someone who has good recommendation vs trying to find a guy next door....