I agree with Quality Home Brewer. I will almost always make a starter even at 1.050 and use 1.0 pro Brewer or higher from the menu. I have used 2.0 for high gravity lagers, and it works. I get a fast fermentation and a very clean beer. Dropping one package or a vial into the fermentor will get beer and if it is a hopy higher temp. (70 F) fermentation, you will not be able to tell much difference. But, if you are making a cold fermented (50 F) clean tasting beer you will. The is lots of very good information on yeast and fermentation on this site and in Chist Whites book “Yeast”. This is probably the next step in brewing after mashing.
Tom McLean
On The Wet Coast,
After the Storm,