The informations about pick up locations etc are a little approximative, I asked Vexere where we could get to the big bus directly and at the end the location was still a mini van pick up that brought us to the bus but that is not a big deal. We left on time from Hanoi but made a very long break at the airport to wait some passengers I guess and arrived only 30 minutes late in Sa Pa so very good. There is no WC in the bus so think about it but you’ll do two 30min breaks in freeway area (3k dong to use the bathroom and they are very clean) and will also be able to buy a lot of different snacks and food. Very confortable seats ! Keep in mind that sometimes the quality of the roads is not that good so it can be very shaky. We booked the top 2 seats at the very back of the bus and you can feel the bus vibrating a lot, the lower seats just before these seats were much more confortable and we were able to use them as they were empty. Overall a very good journey :)