Five friends and I went for this trip, which consisted of a 2D1N climb up Fansipan and a 2D1N cruise at Halong Bay back to back. The services provided by Amity Smile travel were great, and we didn't experience any majorly upsetting hiccups at any point during our trip. Each aspect was well covered, be it miscellaneous transport arrangements or the train accommodations or the porters and guides for the trek.
We had a delayed arrival to Hanoi airport, and although we could not find the agent with our placard (perhaps they could have better monitored our flight times) the agency was easily contactable, and we soon had our transportation. The overnight train ride was an interesting and novel experience, the beds were decently comfortable (king express, soft sleepers) and it wasn't too disruptive to an actual good night's rest. We got scammed of SGD36 by a 'helpful' porter along the way though, highly unpleasant but a good wake up call to be more vigilant and street smart. We then took transport from the train station at Lao Cai to Sapa, and had breakfast at a hotel of sorts (not sure how many stars, if any), but the pho for breakfast was the best we'd ever had, and best meal on the whole trip.
Then came the climb itself. The guide, Chay, and the porters whose names I sadly cannot remember, were quite skilled and helpful during the trek. They were slightly younger than us (we were all around 21) but they danced amongst the rocks and roots with the agility of a mountain goat. The accommodation on the mountain was better than we'd expected (but then again we had terribly low expectations) and the food was pretty good. They also added some bamboo they had cut along the way as a dish for our dinner, which was rather tasty. Some parts of the shelter had holes though, but it didn't really bother us in our sleep. There was some animal (likely a cat) scratching on the roof which was first freaky then just plain annoying. The rest of the ascent and descent were fine, apart from the amount of waste on our path due to construction work as we neared the summit. That was probably the most disappointing part of the trip. The cable car and all that came with it really kinda soured the experience a little, but it couldn't take away the joy from reaching the summit. After the climb, the different aspects all the way back to Hanoi and to Halong Bay were all well covered, except that some prior warning could've been given to us that we would have to find our own transport from the Hanoi train station to the hotel upon arrival. But it was great that the agency could provide us with services for back to back itineraries.
The cruise (royal palace) was a breeze, with another great guide, good quality facilities for the various activities, great food, which made for an all round enjoyable experience. We actually got bumped up to a higher class boat from what we initially paid for (initially supposed to be the Imperial cruise), which was a lovely surprise. When we returned to Hanoi, we found out that our hotel rooms had also been bumped up one class (deluxe to superior or vice versa whichever was higher) which meant we spent our last night in Hanoi in very spacious accommodation. Fantastic end to a fantastic trip.
TLDR: good coordination from agent, damn fun.