I decided to use veg rennet on this one, and I am most pleased with the result. No bitterness, very smooth and creamy flavor. The PB bacteria was pretty old, so I am surprised at the nice holiness! The cheese is not quite as nutty as I would like, but my husband enjoyed it and usually he turns down "swiss" type cheeses. This was a 3.75 gallon make (Jersey and a little goat thrown in because I had some) made August 4, so it is almost 4 months along. I think half will go back for longer aging.