Can anybody give me some feedback on the Navalai River Resort in Bkk ?

Stayed there. You can see reviews at Agoda. I booked based on the many glowing reviews, but here's mine:

Room: River Breeze Room was advertised as a River Breeze room, but little breeze could get to it due to the surrounding (old) buildings. Also advertised as suitable for honeymoon couples. Maybe if they are on a tight budget, but not really a romantic place or room...your basic hotel room with decent tub and fixtures. To be fair, it is Bangkok, and the location is not bad. It is very near the pier and river taxi's, which is a good and bad thing. We could hear the control whistles from the taxi's starting early in the morning through the evening until the taxi's stopped running. The staff were friendly and helpful, which I expect in Thailand. Many of them spoke excellent English. The restaurant was good if not spectacular for paid meals. The breakfast buffet was about the worse for any hotel I have stayed at in Thailand. All pre-cooked, no variety in a week, and even the fruit, such as it was, was not ripe at times. (and if you visit Thailand much, you will know that this is really abnormal) I've read what others here have written, and chose this hotel based on those reviews. Maybe I am more picky, but this was a decent plain old hotel room, and was certainly not anything spectacular. Shopping is a taxi away except for the street markets a block over. The hotel can get noisy at times. Our room was on the second floor, and was near the walkway and the restaurant. We knew people were about constantly, and when the construction downstairs started up, the saws sounded like they were right outside the door. It was an interesting week. Would I stay there again? No. Would I recommend it? No.

It really depends on how picky you are. I am picky. I hope it helps.