My current band (of 4 yrs) has been all IEM for about that long, and wireless too.
We use customs from Ultimate Ears and 1964 Audio (EU7's, A8's, A12's...).
No matter where we play - and we've done over 300 gigs together - we run our own monitors.
Dual band router (Archer C7) connected to an X32 rack, housed with the Senn G3 IEM transmitters. There's also a 16-ch splitter in the rack, with one leg hooked to the X32 Rack. The other leg goes to FOH snake if provided.
If we have to give the house an L/R feed, or we use our PA speakers, we have an X32 Producer that the other leg of the splitter is connected to and we use it to mix FOH. The producer is connected to the sams router (different static IP) so we can mix/run FOH remotely.
We always connect to the snake.. and use our own mics and cables.
We mix our own IEM's from iOS/Android devices using the 5Ghz band - which keeps us out of the 2.4Ghz soup at most venues.
Our IEM mix seldom varies, and we let FOH do what they do.
My rig is Senn G3 to 1964 A8's.. couldn't be happier with my sound.
I keep levels low and the ADEL ports in the IEM allow "bleed", similar to ambient ports. If I turn up, the bleed goes away. That bleed gives me the "room" feel, so I don't add reverb or ambience of any kind to my IEM mix. NO AMP on stage, BTW.
Yes, adjusting to IEM's takes a while.. but I've practiced at home for years using phones (still do) so the move was a no-brainer.
I've been using IEM's at church for about 5 yrs too.. Wired, but with both Aviom and Behringer systems on stage.
When I sub with other bands and we use wedges.. it's REALLY WEIRD.. Can't hear half what I need (want?) to, and I'm usually getting crushed by the drums.
GIVE ME IEM's, any day !!!