In reply to Trangia:
As a new MIA, i have found that i've picked up that type of work quite quickly. Manly due to working for local providers for the last few years as ML/SPA, so they knew me well. Then when i passed, they started putting that type of work my way straight away, which was great.
But as others have said, i think you'd be hard pushed to work full time with just MIA type work. A lot of the days i do are still ML/SPA type days and i'd be surprised if there were many MIA's out there doing purely top end work.
While i agree that there seem to be a lot of people going through the scheme, there is still an amount that either only do training (for personal development/ find that they bit off more than they could chew) or try for assessment and then don't complete after a few deferrals. Added to the fact that there is a boom in the outdoors and climbing especially, i don't see it becoming over saturated.
Also to reiterate what other have mentioned, about the breadth of what the award allows you to do course provider/ tech adviser/ leading courses/ management roles. A lot of these won't be avenues that can be taking immediately as they presume qualified and experienced MIAs. But are doors that may open up down the line.
I'd recommend going for the course if you're thinking about it. Whilst it is a lot of money, you will learn a lot (i thought i knew a lot before i went on the training, and learnt LOADS!). You get 9 days with experienced Guides and MICs showing you loads of tricks of the trade, and you can ask them loads of questions (including their opinions on this topic). So well worth the money, even if you don't proceed from that point.