no one has said it yet... so I guess I will. I've been kegging for close to a year now I guess, and my choice is other.
I use sanke kegs. There are plenty around and various sizes to chose from based on your particular need. Generally of course I stick with the sixtel since it works perfectly for the 5 gallon batch at 5.17 gallons of capacity. There are plenty of ways to source them with some being more legal or moral than others (not getting into that). I think by now I have 3-4 sixtels and a half barrel that I own and 1 or 2 sixtels and a half barrel that the beer distributor owns which need to go back when i go to get my next keg.
My other ideal preference, if I am running low on beer for one of my taps, I can simply run out and pick up a keg of whatever I want and throw it into my keezer and not have to worry about connections. Likewise, I can bring a keg with me somewhere and as long as the destination has serving methods, more than likely, they're set up for sanke's.
Then the argument of cleaning comes in to play. To completely disassemble, clean and reassemble the keg, it might take me 20 minutes of work. I can generally get the dip tube out within a minute and re-assemble just as quick. The rest is just filling and soaking like every other keg.
Also, if you investigate closed system, pressurized fermentation, there's more reasons to utilize the sanke keg...
Just my $0.02...