We had two at my old work, and both were shocking, I worked on many cars and the majority had blobs and marks still left on them

The one who did my Fiesta Zetec S left several blobs and marks on it, which I told him to get rid of straight away, which he reluctantly did. Further more, He decided racing my recently purchased car around the compund was a good idea....Managing director didnt take it well, and me especially not, he got the sack.

Thats my experience though, as said it will be down to the guy doing it, prefferably someone with a sense of passion for his work.