I never feel let down, but when I pump I can see that it usually takes up to a minute or more and as much as two minutes on my right side. I just got a brand new Medela Pump in Style Advanced, which has 2 modes (the fast sucking in the beginning and the long slow sucks), and I let down so much quicker now, it is amazing. I've always had slow let down, but with this new machine, I can let down in under 30 seconds usually! I had an old Medela Pump in Style before (1995, and on the 3 kid), and my new one is so much more comfortable and quicker. Anyway, relaxation is the key.
With the munchkin, one minute or so. Pumping, forever. Lately I've been having ds suck until the letdown b/c otherwise it never happens. I even got an electic (thinking the manual pump was the problem) but it hasn't solved the problem. Bummer.
Before I can even get him latched on I'm POURING milk... ARG! Wish it would take a few minutes, personally cause I'm so new to this breastfeeding thing, and both of us end up soaked! I get the giggles seeing poor little Micah with milk all over his face. He's too cute... LOL