idk, my drip p-tex jobs look pretty good. You just have to not be sloppy (use metal scraper to catch rouge drips and keep the candle close to the gouge). When finished, scrape the overfill flush with a plastic scraper and brush with a wire brush to structure.
also, are you sure the shop didn't "weld" the gouge? Welding p-tex doesn't leave residue.
This^^. I use the metal scraper to both catch drips and clean the repair. Starting in the middle of the repair just use light pressure and start scraping. Once its all leveled off I use a brass brush to structure. Then wax. Now...If it is a deep core shot, Id take it in and have it welded or soldered in. The drip candles are not as effective for larger repairs.
Also...black seems to bond better. Use black.