I avoid bad coffee - anything by Nestle or similar. My coffee at home is better than average but I long for affordable single estate blue mountaun coffee. I had some in the US, it was smooth as silk and the best coffee I've ever drunk.

In terms of Starbucks and Costa Coffee et al - they're an average, middle of the road mass produced coffee vendor. Their coffee isn't bad, it just isn't very good either.

At the moment I am drinking Lavazza and hating it. Next up is Taylor of Harrogate Columbian blend for cafetiere.