This is so true and unfortunately I learned it the hard way. 2 years ago I made a Porter that had a wonderful rich chocolate flavor and I have not been able to reproduce it. I didn't write down whose chocolate malt I used because at the time I assumed they were all fairly close.
Since then I have tried using Simpsons (430L), a generic English chocolate from NB (400L) and Briess (350L). None had the same flavor. Both English chocolates were very roasty.
Does anyone have a favorite chocolate malt when they want a rich, but not roasty, chocolate flavor?
I use Fawcett for chocolate and pale chocolate.