So, while we're on the topic of kegging:

Who all ferments in a keg instead of in a carboy?

Advantages:

1. No narrow carboy neck to make cleaning out the krausen difficult

2. No need to use an auto-siphon to rack for secondary:

I use a 3/8" line with liquid-out ball-lock connectors at each end apply co2 pressure to rack into the secondary/serving keg. Primary fermenting kegs have the dip tube trimmed 1/2" or so in order to leave the yeast cake in place during the transfer, serving kegs do not. This makes for a closed system with no introduction of oxygen during the transfer.

3. No need for a bunch of carboys taking up precious storage space when not in use. Of course, it means I have more kegs taking up space, but I don't seem to mind that as much. :)

4. I've had good success putting leaf hops right into the keg after racking into secondary and then just being sure to drink the beer before it gets grassy-tasting (seems to take a couple months or more to happen). They just float on top and don't gum up the works or introduce foreign objects like socks, metal tea strainers, artisan rocks, or the hair of virgins into the beer.

Disadvantages:

1. Can't see into the keg for any visual cues as to how fermentation is going.

2. Buncha kegs lining the wall of my living room because there's nowhere else to keep them in my house. I think it makes for intriguing decor, but they do impart a certain frat-boy vibe when I was going for "Angry Scientist."

For an airlock, I either plug a regular plastic one into the vent hole of a black rubber stopper made to fit the keg opening in place of the keg lid, or I'll close the keg up and run a 3/16" tube from the grey "gas-in" connector to a flask with some shoe vodka in it.

This has worked great for the not-quite-a-year I have been brewing.

Any reason to use carboys in place of this setup?

Anyone done it both ways and tasted a difference?