I have used in-ear monitoring for years.
I would like to caution YOU: USE SOME SORT OF LIMITING DEVICE IF YOU PLAY LIVE!
If there is feedback, you can really damage
your ears.
I use the ,now dicontinued, "Boss LM-2" Limiter; so I run the PA monitor out to the LM-2 and to a Roland TM-3 headphone amp and
then to my headphones. I never got into
wireless and don't find it necessary since
I don't roam on stage.
Good luck.