Hi Charles,
Our lead cheese maker Helen Cowan says, “ Any rennet should be fine - the key to Limburger is getting the texture of the curds right (after the cut step) and then washing it to develop the rind while aging. We like traditional rennet because cheddar is aged longer and develops more complex flavors over time - which is definitely affected by the trace amounts of rennet left in the cheese. With a younger cheese like Limburger it won’t be as noticeable.” Hope this helps!