I brewed last Sunday. Everything went very well. My only problem was that the instructions called for 1/2 oz of the various hops additions but the packets each contained 1 oz. I completely didn't notice until after I added them to the beer so I guess it'll be a slightly hoppier ESB. Not a problem for me! In the end I hit my target gravity of 1.060, which doesn't seem like a surprise since I'm using malt extract.
One thing that may be a problem is the lack of fermentation. I had a "smack pack" of liquid yeast. I warmed it up to room temperature 12 hours before I brewed and smacked it to break open the inner package 3 hours before I brewed, just like the instructions said. It was supposed to swell up but didn't. The package also said that if it doesn't swell then it isn't a big deal and to use it anyway. So 3 days later, still no fermentation! I opened up the bucket last night and remeasured the gravity - still 60. Not even a little bit of fermentation has taken place. And ale is a top-fermenting yeast. I saw nothing floating on the beer. I'm suspicious that I got a bad batch of yeast. The instructions in the kit from Austin Homebrew said to call if I see no fermentation after 48 hours. I'll call when they open today.