All of the mushmom's give good xp and i think all of them have a low chance of dropping a set od llbi'is (not 100% bout blue mushmom) but recently there was a x2 xp + drop and i got from lvl 25-30 in an hour + 2 sets of llbi's from surfing channels and running between zombie mushmom and blue mushmom but without the x2 drop and xp... i rekon on a low populated server (like el nido) lvl's 27-30 is a good idea to zombie/blue muhmom just cuz you can kill her fast and its 1,600-2,000 xp a kill...