lol - do some Googling and then come back before you criticise. Just how big is the order book for Merlin? Boeing are inundated with orders right now, keeping the price to a minimum. Admittedly, that might impact delivery timescales, and oh of course we also have to keep British industry ticking along. Not getting into a fight about which is better, just IMO new Chinook are likely to be cheaper and provide greater flexibility than Merlin.
We do all get carried away with having a specific UK-capability - buying off the shelf and doing the bare minimum to integrate is so much cheaper. The Mk3 was over-specced and over-complicated, hence the absolutely essential (never suggested it wasn't) safety assessment has kept them grounded - DPA specced it and ordered it - whose fault do you suggest it is?