Four season s is the best from that list followed by the Fairmont. I would go with the Fairmont for location. If spending a lot of time in 5he hotel, Four Seasons is a better choice.
Thanks for quick reply.
4 seasons also the most expensive, typical but I guess you get what you pay for.
Is Fairmont a good location even if we aren't really interested in nightlife? We will be there just for a 3 night stopover on the way to New Zealand and are mainly interested in sightseeing and food
Fairmont is perfectly located for what you want. Plenty to see and do within walking distance and also above an interchange MRT station for getting about.
You can't go wrong with the Fairmont: the location is great, right on top of City Hall MRT station so moving around is very easy. Marina Bay is 1 station away or you can just walk to there.
Fairmont is in a good location and you can indeed walk to some places from there.
There are some interesting boutique hotels in Singapore; for example The Scarlet. It is close to Club Street and Chinatown, and many other places to eat, including Maxwell Food Centre. A drawback is that, while they have a jacuzzi, they do not have a swimming pool. But the premium rooms are big and the hotel is very nicely decorated. You might check out their website.
(It is also close to an MRT station, but since you are "... mainly interested in sightseeing and ..." I think that probably you would rather take the (inexpensive) taxis that abound. Trust me, you can see more when above ground than you can from the window of a subway.)
Hanks for all your replies, very useful