On my way back from a 1-night 2D cruise with Handspan / Treasure Junk.
Booked in Hanoi the day before and got the single supplement waived so US$177 all-up.
Could not fault them.
Well appointed moderate sized boat with 12 cabins and 2 suites all with own bathrooms, and a lovely sun deck with sun lounges. Staff of 22 on board and all of the meals (5+ courses each) were exceptional. Alcohol at US3 a beer US6 coughtail and range of wines from US20 (local) to US35 (French, Aus, Chile).
Importantly the boat takes a longer Eastern route and overnights in a more secluded bay with only 5 other boats, so you are well away from the party boats. Decent kayaks included as part of the package. Only time cruising we saw other boats was at the start and end and during visit to one of the smaller fishing villages and pearl farm.
Transport via a 25-seater minivan that was at most 15-ppl with only a single 20min stop at marble center/art shop/restaurant