A barrel is a dispensing system.   You will get a degree of carbonisation which is just right for dispensing your beer.   Pub lagers are heavily carbonated, so if you want this effect you will need to use bottles (I prefer lager less fizzy).   The problem with bottles is that it is a pain washing,sterilising, filling etc. etc. 40x pint bottles and you will soon lose interest.   The answer is to use bigger bottles    If you do not drink a whole bottle in one go then reprime and move on to the next bottle (come back to the 1/2 bottle when it's repressurized).