I notice it when a gal goes to the effort to make the experience terrific, and it can make a good experience very good, and a very good experience great.

That said, I've had some sessions in a 2 star that were better than some five star experiences, because ultimately it is the gal herself that is the main factor in how well the experience goes.

To use the metaphor of a restaurant:  It's all well and good to have plush seats, silver, crystal, soft lighting, and music, but if the food sucks, I'm not going back.

On the other hand, a great meal in a shabby run down diner is something I'd go back to again.

GFE can be dangerous on so many levels, you do not know if the girl has anything,  
In  some cases she could have all types of viral diseases that an than be spread to your mouth..  
think about that the next time you ask for GFE .. just saying..

RE: Does the quality of the incall

The hotel need not be too fancy; equivalent to like a "Holiday Inn" is fine.
More important is the ambiance, just like you mentioned.
Often, I will bring the wine and she supplies the candles, music, etc.
The lady and the "mood" are more important to me than the #stars the hotel has.