Keg vs. bottles&cans

I would personally do bottles instead of kegs. I would purchase cases of bottle beer as it keeps the flavor better than can. That also gives you more options to choose from.

For 50 people, I would go with cans/bottles. We have 50 guests also and were thinking of getting a quarter keg until we found out that you have to rent the tap, and buy a bucket and tons of ice to keep it cold from the moment you get it. It seemed like way more hassle than it's worth. Not to mention, if you don't use it all, it just goes to waste. Whereas, unopened bottles will last for months. Another plus, is that you can have more of a variety of beers with bottles and it's cheaper than a keg.

I would purchase cans/bottles from a place that will allow you to return unused/unopened product. This way you can be sure to have enough on hand without having to worry about over buying. I also agree that doing a keg is too informal for a wedding unless it's a casual outdoor BBQ or barn wedding. Besides, if you don't use all of the keg, you're out that money anyway. With the cans/bottles, you'll only pay for what you actually use in the end.

I'd do the bottles. If you guys aren't big drinkers then leftover bottles can be saved for later but a keg will go bad at some point.

Also bottles give you the opportunity to offer your guests a lot more selection.

With kegs, you have to think about how you'll keep it cool, and how will serve guests since some people have a hard time if they see a keg and have to serve themselves (if they've never used one before because they don't drink a lot). I'd opt for bottles & cans. You can also get more options and don't have to worry about returning the keg the next day.

I would opt for bottles for sure.