All koelsch are the same, remarkably little variation between brands (all good, and an interesting difference from other beers). A few hours is enough time to drink 8 beers (unless you aren't pulling your share, or heaven forbid driving).
An interesting development in Germany is the rise of microbreweries, many of which don't bottle their beer (you can only drink onsite, from the tap, or bring a thermos and they fill it up). Some of the best beer is in this category (perhaps not surprisingly).