When I'm working in Bristol, I usually stop in at Java J's for coffee and a Panini. The coffee is as would be expected. The sandwiches are good but take quite a while, so this is a place to eat if you're not in a hurry.
Java J's has a big backroom area with couches and tables and is a really good place for conversation with a friend or business associate. It isn't the kind of place you would take someone you're trying to impress. Rather, it is the right place for to go with someone you have a good relationship with and want to enjoy the atmosphere with some good coffee. It's also a good place to work if you have a laptop and need WIFI for an hour or two.
On the food, their specialties are the Italian Gelato, which is somewhere between Ice Cream and Sherbet. The Paninis, as I mentioned, are very good. They also have good fruit smoothies.
Be advised that on Friday nights they usually have a loud band which makes it impossible to have conversation.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.