I had issues early on when running 3.6. I got the 3K tail blades and made sure the tail was super smooth and managed to get it working well. Since I upgraded to V4 the tail is working very well. Same tail blades and no issues.
FYI I wasn't happy with the amount of cyclic and collective I was getting with the align balls on the grips and the resulting reduced standoff from prior to the crash. I moved the servo balls in 1 hole on the arms and redid the setup. Much better servo resolution now and the throws are more reasonable. The vbar numbers are much closer to where I was before now too. Had three more flights this evening and it flys great.