So after a good while of using the system, I feel I can give a decent account of performing with it. To recap, it's the LD Systems MEI One wireless UHF In Ear Monitor I bought second hand from Gumtree. I wont include pictures to save space. Just refer to the previous post for those.
Setting up during soundcheck is easy. The Mackie DL1608 our regular sound engineer uses is easy to work with and with the sender unit set to mono, all it takes is a 1/4" jack to jack from aux to left input and that end of things is ready once plugged into the mains and the arial screwed in. Only problem is that if the stage power goes down (which happens an unfortunate amount on outdoor stages) then the unit needs to be turned back on again. This is no big problem, but if you or the engineer don't realise it can lead to a confusing bit of trouble shooting.
The belt pack takes 2 AA batteries and is pretty good for consumption. Averaging about 4 x 2 hour shows before showing signs of death. There's a LED onboard to let you know you're running low so keep a spare pair in the box! The pack is light and has a belt clip, no more bulky than any of the others I've seen. The only problem with this is that the rubber volume knob on top seems to catch on my clothes occasionally and turn the volume down which is a mild irritation! Other than that, the rest is all good and I've not had any signal dropouts, lag or poor sound.
Ear buds however are another story. Whether the drummer I bought the kit from ran them at high volumes (don't worry, I did clean them thoroughly,) or whether they sounded like they do out of the box I'm not sure, but they aren't the best sounding examples. The top end lacks some crispness and the bass power isn't great either. They can pump out the volume for definite and you can hear what you need to over even the most ridiculous of stage sounds, but you're not going to get the delicate highs and lows. I've tried them on other devices and they do still sound the same. Still, the isolation is good and I come away from shows without ringing ears and having had a damned good monitor sound. Most irritating however is the fitting. The driver housings are metal and this means weighty, which means quality right? Fine, but when the ends are the same kind of rubber that the cheap high-street buds use, you find them falling out mid-performance at the mere hint of sweat or movement.
So, the supplied buds are fine, but if and when I have a spare £300-500 I'll definitely be looking at the Shure SE range. I've heard nothing but good things about them from session players and with 3 drivers per ear and an over ear fitment on the 535 model (Pictured) I believe this will make the whole system work on a par with the Sennheiser units still for a much lower price overall.
To finish, the iPhone compatibility with the Mackie sound system via the Mackie app allows me to manage my own monitor mix live. We've had a few teething troubles with mismatched updates between devices, but overall it's been fantastic as no-one is better suited to getting the mix I want than me and avoids the usual back and forth for fine tuning.
I'm definitely enjoying the fact I'm getting the mix I want when I want and protecting my hearing at the same time. Band mates occasionally say they feel I'm more isolated with them in, but I think it's something to get used to and learn to work with as my ears are important to me. Happy hearing!
Dan
@frame_boy
However I saw the Java Reds on Reeds-Direct.co.uk and gave them a go. They have an amazing balance of power and finesse, being great for both hard funk and smooth jazz. They bed in and warm up quickly, but like all reeds you do get some duds in the box. At the moment of writing on average 1 or 2 per box of 5 warp the minute they're wetted or are woolly sounding, but the rest are sharp and clear. 
