Yes is worth sacrificing one of your dps trinkets for devilsaur, especially if it's something like trinket from Star Augur or Fury of bruning sky. Personally I swapped my 905 methronome for it and left with whispers + devilsaur. If only I had that trinket from Tree in DHT so I could use it + devilsaur. As of effigy, I ended up running in pretty short circles so I could probably use it, but I find it more useful to use PS for 2 and 3 phases(and it could also be used twice on first phase).