The best bar for me, is any bar that I visit in Prague. Not only is the lager some of the best in the world, produced more like real ale than the chemical rubbish offered to Brits, but it's less than £1 pint (.5 litre). Was even better the first time we went in 1995. Beer was approx 16p, and if you were charged 20p, you were being ripped off.
There are numerous great bars and great beers in Prague. Most bars are no nonsense, if you avoid tourist places. Always busy, because drinking beer is the number one hobby in the Czech Republic. Mainly blokes, just talking and servers regularly visiting your table with fists full of foaming mugs. Occasionally a small shot of fire water to go with the beer. Just as it should be.
And, you can still have a smoke with your beer.