I'm reviving this thread, so I don't need to start a new one...
I have a porter that is fermenting right now in the basement. I didn't realize how cold it is down there. I looked at the temperature strip on the carboy, and it's about 56 F.
I pitched 2 packets of rehydrated US-05 at 68 F. It took about a day to get going. The krausen is pretty thick (3-4 inches) and fluffy...makes me want to jump into a pool of milk chocolate and marshmellow. It does seem like it's taking much longer for the krausen to drop than most of my other beers.
It's been about 10 days, so I think I'll move it out of the basement into the kitchen where it's warmer for the last days of fermentation. I'll report on the flavors.