The ACS Live are not expensive when compared to the overall market.. actually quite reasonable @ $700.
If you want expensive, look at 1964 Audio's
A12's ($1999) or JH Audios
Layla's ($2500).
If you are going IEM, and to have it work for you, IME you need: -
- Multiple driver IEM's (preferably custom fit) to get instrument separation, clarity and definition
- STEREO IEM feeds to assist with the 3D spatial image and separation,
- Control your own IEM mix or have a dedicated monitor engineer.
- If wireless, then quality wireless system (PSM900/Senn G3 or equivalent) to match quality of other components
I run 1964 Ears Qi's (quad drivers) and have a Senn G3 IEM wireless rig. My current band has an X32 Producer console that sits in a rack on stage, along with the IEM transmitters. Power amps are housed in a separate rack. Whether we use the house PA or our own, everything (drums, bass, guitars, vocals, etc) is connected the same way - either DI or mic'd - with splits going to FOH as needed, and IMPORTANTLY,
ALWAYS connected at every gig!!
We use a variety of iOS/Android devices that connect via a router to control our own stereo IEM mixes (using the X32Q app) and FOH when not using a House-provided PA system. We have backline amps, but whether we play a large venue with provided FOH/PA or a small venue like a Private Party - our IEM mix is consistent, and we adjust for FOH as needed. Obviously, one doesn't need lots of guitar. bass or drums in a tiny venue, so while mic'ed/DI'd, they may or may not be present at FOH, but they ARE ALWAYS hooked up for consistent monitoring. NO stage wedges in use.
Things (wireless regs) may differ in the UK tho'.. the above is US specific.
UPDATE: We tried the ambient mic thing... found it caused more issues than it resolved, and dropped it. One simply needs to get used to using IEM's.. and there are many ways other than what I outlined above to make that happen. Like the Axe, quality gear isn't cheap.. and I've seen plenty of guitarists who simply cannot adjust to the "recorded" sound versus the amp-in-the-room they are used to hearing on stage.
Many never adjust...