Advice? Royal Grammma and Fourline Wrasse

I have a royal gramma and 3 green chromis in a 40 breeder reef tank with 50+ pounds of live rock. The royal gramma is pushing 3 inches. I have a fourline or as some call them twelve line wrasse in QT. I have read all kinds of posts of people having problems with there royal grammas and SIXLINES not getting along. There's not alot of mention about the compatibility of four/twelve line wrasses and royal grammas. Was wondering what opinion does anyone have about the fourline wrasse and royal gramma. Don't want to make a mistake.