I bought a pack of Mangrove Jack's U.S. West Coast Yeast, and I thought I'd share my experience. One caveat however, is that this is my first experience with dry yeast. I typically use liquid yeast with starters.
The best buy date on the package was 9/2014. It is supposed to be adequate for up to a 6.6 gal batch of wort under 1.050. I followed the manufacturers re-hydration instructions, http://cdn.shopify.com/s/files/1/0195/8 ... t.pdf?1935, which states to add the entire package to 100 ml of water adjusted to 86-95 F water and stir for 8-12 minutes, then pitch immediately.
Since I was only making a 4 gallon batch of 1.046 wort, I used Mr. Malty's calculator and only used 7.5 grams of yeast re-hydrated in 750 ml of water. (my plan was to slightly over-pitch, just-in-case)
I cleaned and sanitized a small beaker, and then rinsed out the sanitizer with previously boiled and chilled water, heated it to around 95 F, and added it to the beaker. I checked the temperature in the beaker to make sure it hadn't dropped too much, added the yeast, and stirred for 10 min. I didn't pitch immediately, but after about 15 minutes, and definitely before 30 minutes of re-hydrating. I oxygenated with oxygen for 1 minute before pitching, and the wort was at 66F checked with a thermowell.
I didn't see visual signs of fermentation until around 18 hrs, definitively after 24 hours. Krausen formed after 48 hrs. and high krausen after 72 hrs. It's still fermenting now after 4 days, and I'll keep updating.
This was the slowest fermentation I've had (I usually have vigorous fermentation within 12 hrs.), and depending how this beer taste, I probably will stick with liquid yeast. I'm assuming because of the slow start I might have under-pitched. If I do use this yeast again, I might consider using the Yeast Books re-hydration instructions.