on one hand it is ment to be a good way for a company to lower the price of it's goods to the consumer without worry that some middle man will take the price difference as a reason to get a larger proffit on the item, But unfortunitly, I find that in practice, it is not worth my time to chase them up, worry about issues like "not received on time" or "offer expired on..." or "you did not cut the barcode out properly" ect. Easier (and less hassels) to just find the best price and ignore rebaits.
If I knew someone that would do the leg work / process my end of the MIR, I would proberly just sell the MIR claim code to them at 20c in the dollar.
Seeing as their are buinesses to do the MIR from the manufacture's side, and that there are ebay listing companies, I am suprised their is not someone doing MIR's from the customer's side as a business.
I suspect it is either against some MIR rule or more likly, their is no viable business model for doing it (as most MIR's do not get claimed).