IEMs are only good if your gigging situations meet these criteria:
1. You have a competent soundman who can provide you with your own instrumental/personally tailored mix to your IEM unit.
2. You have more than 10 minutes to set up your gear.
(I'm the lead vocalist, so my requirements are different than if I were just a guitarist/backup vocalist.)
Most places that WE play at, if you're not set up in 10 minutes, you run the risk of decapitation. And when you ask the soundguy for a feed from the board, even if he knows what you're talking about, most times they won't oblige. They'll just be like "uh, no, we can't do that." Cuz they're lazy.
I tried to have it set up where my vocal mic line went thru the IEM system. THAT worked great. But trying to use
a SM58 on a small tripod stand as a "stage" mic... just didn't work. I felt really isolated and lost up there.
My solution:
a Shure Beta58, bring it to every gig, eat that motherf*cker like an ice cream cone, and crank the monitors. I can get them ALOT louder before feedback with the Beta58.