Ive never used a TFR on any of my customers cars,never had a problem removing dirt/grime without it
Its all about putting a decent wax/sealent on there to protect the car from everyday grime
Most car washes are are no better than monkeys
I had a call in the summer from a guy with a black range rover,he took it to the local car wash because it was covered in what he called (bumps) he didnt now it was tar from a new road surface near his house
They cleaned the car but didnt remove the tar and they sprayed some kind of wax over the tar doh!
Took me 2 hours to just to remove the tar,i now valet all of his familys cars every month
I also valet a car for the land owner of another car wash in the next town,he works next door but still calls me in to do his car so they cant be that good!
For a quick wash for a everyday shitter they are fine,if you have any decent i wouldnt go anyware near them