Most regular folk checking out reviews of this hotel will probably be debating whether it is wise staying in an establishment branded as a "brothel" by many. To address that immediately -- my answer is that I never encountered any unpleasantness, noise, or sleaze during my 2 nights stay there. Avoid floors 3-4 (most tourists are put on the highest 7th floor anyway) and you wouldn't even realize there is a massage parlour in the building.
Location was perfect for me --away from the hordes of backpackers and tourists, in a very central but more local/Asian area. Perhaps for first-timers to PP, closer to the riverside or BKK lake might be better and more walking-tour-friendly, but repeat visitors familar with the city should find it easy grabbing a moto/tuktuk and explaining a destination (the drivers around here are cheaper but less likely to speak english).
Paris is a very "Asian-style" in feel, in the way that it focuses on the neccesities (cleanliness, price, convenience, safety) rather than the more "European" concerns of atmosphere, slick service, and family-friendliness. (I'm Singaporean Chinese, so I empathise with both camps).
The rooms are enormous for the price ($18) but quite spartan with harsh flourescent lighting, ancient wooden furniture, a firm bed, and a noisy air-con. Cleanliness is top notch though, an amazing feat given the age of the building and fittings. Shower is fine with real hot water and a bathtub to stand in (not to soak though). Two free bottles of water everyday, and replaced soap/toothbrush/towel too. Staff are extremely friendly and helpful, but may require a smiling, patient, non-condescending approach first, like anywhere else in this part of the world (something many of us tend to forget sometimes). TV had tons of channels including English cable and some channels of DVDs played in-house.
The disadvantages:
The duvet is flimsy and did smell a bit musty and could have done with a wash -- this was perhaps my biggest gripe. Aircon was slightly noisy but I was too lazy to change room (I got 707). Window drapes don't block out sunlight well so room doesn't stay completely dark in the morning.
All in, this is fantastic value for money at a level I have not seen anywhere else. If you can live with the small disadvantages, choose this place, and if you can't, prepare to pay at least double for a slight improvement. This hotel is off the typical backpacker/Lonely Planet traveller trail, and is all the better for it.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC