I personnaly, although a huge fan of Pen hotels in the world, have never understood all the ranting and raving about the Pen BKK.
I must say however that airport transfer and assistance (I had booked the RR) where great in and out (as good as in HKG).
Check-in in the room was fine, no room upgrade (LC) and they insisted on how priviledged I was to be offered (as a member of the LC) the fantasticaly tacky and cheap Pen 75th Birthday lugage tag.
I had trouble with check-out, they told me (or didn't understand my question) that I could check-out at the pier where the car would be waiting, so I did end up having a few trips across the river for nothing.
At the time I was there, it was a fight to get a table at breakfast, a most unpleasant experience.
A great location, with great views. Crossing the river is fun and skytrain very easy and quick as is river taxi etc...
A very ugly and poor modern construction, in the first room I had, every time the shower or toilet in the room above were used it made a terrible noise, I was told that this was normal and mouve to a corner room with fantastic views and no disturbance from neibouring rooms.
I agree it is very good value, but for my next stay this year I have booked the Met, will have to see.