Honestly I don't see why MAS would want 787s, but let's see about the possibilities...
787-8.... Maybe so they have something smaller than A330-300s? Would also provide a long-and-thin plane that could do Europe probably less expensively than an A330-300/900
787-9.... Maybe for longer routes that aren't sizeable enough for the A350s?
787-10... For thicker regional routes that need more capacity than an A330-300/900?
Still I don't see why MAS just doesn't go for the A330-900... the A330-900 could theoretically reach Dublin or even Madrid after all.
The 787s would need to offer much lower CASM to offset the A330neo's lower costs regarding acquisition and staff retraining (or lack thereof).
I have to agree, I really don't know why MH didn't go for the A330neo, it should have been a perfect fit. They've stated they're not really interested in restarting European destinations, and from what I've heard the competition on TPAC is so severe it's pretty hard to make good money. With the investments they made in A330ceo/A350 recently the A339 should have won this contest easily.
But maybe that's one of the reasons. Perhaps Airbus thought this one is in the bag, therefore they didn't discount very heavily and Boeing did? It happened before with Silkair when they ordered the 737MAX instead of the A320neo.
I can't see Boeing discounting the 787-8 deeply though, it's almost as expensive to build as a 787-9, so that one I dismiss.
The 787-9 is a good airplane, but the A339 is pretty close in efficiency. It's would be quite a bit more expensive for MH IMO, and I don't think Boeing would discount desperately low, considering how much cost they need to recover on the 787 program.
Only the 787-10 could make sense, if MH wants larger aircraft than the A330 they are currently flying.
But I still wonder how the 787 could be considered the best option available to MH.
146,318/19/20/21, AB6,332,333,343,345,346,359,388, 722,732/3/4/5/G/8,9, 742,74E,744,752,762,763, 772,77E,773,77W,788 AT4/7,ATP,CRK,E75/90,F50/70