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I have just booked a DONE4 ex-HND using
@madrooster's travel agency. It is a great option at the moment as due to the low value of the JPY, my ticket cost me sub-A$9K, which is incredible as you really can't get a return fare to LHR or LAX for that, let alone RTW. I've also got a side trip to DRW as part of it after I get back to Australia.
I just had to make a CR booking to HND one way to start the trip, and I've got the return to HND flights next year which all going well will be where I start my next DONE4. At those prices, going via Japan is completely worth it. (Ex SYD, DONE4 is about A$16K).
And sure, you can still get a great fare booking yourself via the web (and trust me, I haven't used a travel agent since 2008), but I can say going through an agent like MR is definitely worth it - without going into specifics of what he can do.
For those interested here is my trip:
View attachment 398640
Fairly vanilla, an open jaw in Europe (ZHR-CDG), LHR, JFK/LAS then home. Stand alone trip to DRW (using the loophole that BNE/DRW doesn't count as transcon, but SYD/DRW does).