The rooms are very nice, well soundproofed. As Diamond, no suite upgrade, just a corner room (I have now decided to stop chasing Diamond, I haven't been getting any suite upgrades recently and just don't see the point in it anymore).
The main issue with this hotel is service, it's just very unsatisfactory, especially for a Conrad. At check-in had to ask every little detail: What time is breakfast? When do we need to do the Covid test? No info about the executive lounge timing was given. In the lounge, they forgot half the breakfast order. Room service with PLASTIC cutlery in takeaway boxes, in a 5-star hotel... When I called to request metal cutlery, they said they will bring some but never came.
The food in the lounge is of good quality though. Question is, do you need to have food in the lounge when Bangkok is literally a huge street food market. We only ended up going there 1 out of 5 nights.
Stayed to the Waldorf Astoria the day after and it was much better, so if it is within your budget I would recommend that much more.