Also, Changi MRT serves 2&3 easily, but 1&4 annoyingly (need to walk or take sky train to t1, need to take bus from t2 to t4)
T2 is closed until Nov 2021 (18month renovation since may 2020), T4 closed &reopening unknown
uA is at t3, NH is at t1, but these could change when reopen happens
Having good MRT access is good for day-to-day, but also depends on what you want to do (shopping? Orchard, marriott and hilton and gtand hyatt there, andaz at bugis)
Quite easy to go on google maps and search Singapore+hotel chain, you can easily see the MRT station icon. Click on the MRT station icon and you'll see where the MRT line goes