MM4 / NaB,
You two sound like attendees at a SABR requirements meeting...
The cycloptic muppet and his CS/Military outriders killed the folding CH47 SABR platform 5 years ago with the £1.5Bn raid on the RW budget. Ironically, they'd be arriving soon. Be sort of handy right now wouldn't they?
The imperitive seems to be getting aircraft at the rush - this would preclude any attempt to marinise the CH47F - that boat has probably sailed (pardon the pun..). So, what we're left with, is spending almost as much money 5 years later to buy (likely) inferior aircraft v the SABR baseline (no fat tanks, no blade fold, no wx radar, no wet build etc etc). However, it HAS to be better than buying more Merlin. The final config state of a CHF Merlin would need to be such that it genuinely provides the CHF with an uplift in capability - and a load more wokkas should ensure there are always enough for 2-3 in future TAGs.
The marinisation of the Merlin will probably take some time, but then we've got it. I can't see many fighting a temporary "capability holiday" on Amphib lift if the cabs (SK or Merlin) are doing the job in Afg - hopefully it will give the OEM time to think through the maritime, performance and capability problems.
Oh, and NaB, having operated extensively of one of the war canoes during Ops near a sandy place, I would always chose an air conditioned cabin, head and wardroom over a tent, tent and tent!!