BG 44K is also recommended for "on car" FI cleaning.
Most shops are reputable and will do something similar to the gas tank cleaner when you take it in for service. The 3 cleaners mentioned have been shown to actually work. Shops may have some other equipment to pump things through the system in a shorter time and under pressure, but I'm not sure they work any better than just buying the Techron, Redline, or 44K yourself and following the directions.
I also don't know that taking them off the car will give you an advantage, since now you have to pay even more for labor and special equipment.
